Napstablook's design is that of a simple ghost: mostly black and white, a long white body, two eyes with black sclerae (the white parts of the eyes on normal eyes), white pupils, and a mouth. A thin black line separates the eyes. After encountering Napstablook in Waterfall, they wear a pair of generic black headphones for the rest of the game.
Napstablook is a dour introvert with low self-esteem. Napstablook cries in battle, which may indicate some form of depression, anxiety or sorrow. Despite this, Napstablook is courteous to others and treats the protagonist as a guest when they visit Napstablook's home (even if attacked in the Neutral Route). They often employ self-deprecation and apologize for any inconveniences to be polite.
Napstablook blocks the protagonist's way in the Ruins and pretends to be asleep by repeatedly saying "Z" out loud. If the protagonist cheers them up, Napstablook thanks the protagonist for being so kind and then leaves. If fought, Napstablook admits that they were lowering their HP to be polite before leaving.
Napstablook appears in the center-bottom basement room of the Ruins's six-holed puzzle room if spared in the initial encounter. After the protagonist talks to them, Napstablook realizes ghosts can fly and disappears.
Napstablook does not appear again until the protagonist fights the Mad Dummy in Waterfall's Garbage Dump; Napstablook interrupts the fight by crying tears (mistaken for acid rain) on the Mad Dummy until they run away. After apologizing for breaking up the "fun" the protagonist was having with the Mad Dummy, Napstablook invites the protagonist to visit their home.
Upon arrival, Napstablook invites the protagonist to listen to their music. Napstablook has three playable CDs: "Spooktune," "Spookwave," and "Ghouliday." They also offer the protagonist a ghost sandwich to eat if the protagonist approaches and interacts with the fridge. However, the protagonist cannot eat the sandwich because it phases through them. After this, Napstablook suggests that they lie on the floor and "feel like garbage" together. If the protagonist lies down for 20 seconds, the music becomes calmer and the background changes to a space scene. If the protagonist refuses to lie down, Napstablook exits the house through the right wall and does not return until the protagonist leaves.
East of Napstablook's house is Blook Acres, another location where the protagonist encounters Napstablook. Napstablook is the sole employee of Blook Acres because all of their cousins left to gain corporeal forms. Here, the protagonist can play Thundersnail.
During Mettaton EX's battle, Napstablook is the first viewer to call and express gratitude for Mettaton's television programs, as shown by the typing quirks - missing capitalization, abundance of ellipses and the frequent use of 'oh' - and the way Mettaton says "NO, WAIT BL–" suggesting that he was referring to Napstablook as "Blooky," Napstablook's nickname.
True Pacifist Route
In the epilogue, Napstablook and Mettaton are in front of their houses; Mettaton recruited Napstablook as his celebrity sound-mixer. Napstablook's SOUL was not absorbed by Asriel. In the credits, Napstablook tours with Mettaton, Shyren and Burgerpants.
If the protagonist has exhausted the kill count, Napstablook fades away when the protagonist approaches in the Ruins. Napstablook does not intervene in the Glad Dummy fight, and the protagonist can visit Napstablook in Waterfall if the Waterfall kill count has not been exhausted.
- For an in-battle description, see Napstablook/In Battle.
- Napstablook's name sounds like "Napster bloke." Napster used to be a peer-to-peer file-sharing service that focused on sharing music files before being bought by Roxio. This term references Napstablook's computer being on a "music-sharing forum" and Napstablook's general affinity for music. "Dapper Blook" is a play on the phrase "dapper bloke," which is a British phrase referring to a sharply-dressed person (usually male). "Blook" may also derive from "spook."
- The name could also reference the protagonist's first encounter with Napstablook. In the Ruins, Napstablook is found sleeping directly in the protagonist's path, with no way to go around. That is—Napstablook naps to block the protagonist.
- Another possible origin of the name is the combination of the three words: "Nap", "Stab" and "Look".
- Naming the Fallen Child "Napsta" or "Blooky" prompts the message "............ (They're powerless to stop you.)" and allows the name to be chosen.
- Napstablook and the Dummy are the only enemies in Hard Mode that do not change in difficulty.
- They may be an allusion to "ghost producers," who are composers who sell their works to people who can claim the production as their own.
- Napstablook's face closely resembles the protagonist of the N64 game Glover.
- "Killing" Napstablook makes the protagonist "lose 1 experience point," leaving EXP unaffected. Because of this, it does not ruin a True Pacifist Route and is a hint early in the game that experience points are not the same as EXP.
- Sparing Napstablook does not abort a Genocide Route.
- Napstablook and Mettaton are the only two enemies that use the gray attack, which is harmless and used to spell out words; Napstablook spells out "REALLY NOT FEELIN' UP TO IT RIGHT NOW. SORRY." while Mettaton spells out "Happy Breaktime!"
- The artbook reveals that Napstablook was never originally planned to be in the game, and was just a placeholder character for the Encounter user interface mockups. Toby Fox's friends seemed to like the character, so he ended up making Napstablook real.
- Similar to Sans, Napstablook speaks in all lower case, not even capitalizing names or sentence starters. There are a few exceptions, however. As for punctuation, Napstablook frequently uses ellipses, often with more than three dots (sometimes many more), even at the beginning of some sentences. They also tend to omit most question marks and some periods, while using commas (and most periods) correctly.
- Napstablook, Papyrus, Aaron, and Tsunderplane are the only four monsters who reply to the text shown when they are checked.
- In the Undertale art book, Napstablook used to be referred to with male pronouns. In the Fangamer version of the art book, however this has been changed to gender neutral pronouns.
- In the Japanese translation, Napstablook uses "kimi" to refer to a person, which is usually used by males.
- ↑ Toby Fox [tobyfox] (July 4, 2017). "In ENG, character name pronunciation isn't clear. But in JP I had to decide. Like, "Blook" rhymes with "Spook" instead of "Hook."".
- ↑ "(This ghost keeps saying 'z' out loud repeatedly, pretending to sleep.)" - Narrator
- ↑ "sorry... i just made this more awkward... pretend you beat me... oooooooooo" - Napstablook
- ↑ "i fell down a hole... now i can't get up... go on without me... wait, ghosts can fly, can't they... oh well..." - Napstablook
- ↑ "The door's been locked for ages. So unless you're a ghost or can burrow under the door, forget about it." - Snowdin Shopkeeper
- ↑ "Wh... What the heck is this!? Ergh! Acid rain!?! Oh, FORGET IT! I'm outta here!" - Mad Dummy
- ↑ after a great meal i like to lie on the ground and feel like garbage... it's a family tradition..." - Napstablook
- ↑ "welcome to blook family snail farm... ...yeah. i'm the only employee." - Napstablook
- ↑ "Dearest Diary: Our cousin left the farm to become a training dummy. That leaves just Blooky and I." - Napstablook's cousin (Mettaton)
- ↑ "seeing you on the screen... brought excitement to my life... vicariously
i can't tell, but... i guess this is the last episode...? i'll miss you... mettaton......" - Napstablook
- ↑ "i was just sitting at home listening to tunes there was a flash of light outside my window i saw the snails on the farm disappear then i heard a knock at the door the flash of light wanted to come in... i closed the blinds... now everyone knows your name except for me" - Napstablook
- ↑ "Missed the memo and is the same difficulty as normal." - Napstablook's Hard Mode check text
- ↑ "oh, i'm REAL funny." - Napstablook upon being checked
- ↑ "i usually come to the RUINS because there's nobody around... but today i met somebody nice..." - Napstablook after being spared
- ↑ The Undertale Art Book: Main Characters! - YouTube
- ↑ Tumblr
- ↑ Tumblr
|Main Characters||Flowey • Toriel • Sans • Papyrus • Undyne • Alphys • Mettaton • Asgore Dreemurr • Frisk • Chara|
|Ruins Enemies||Dummy • Froggit • Whimsun • Moldsmal • Loox • Vegetoid • Migosp • Napstablook|
|Snowdin Enemies|| Snowdrake • Chilldrake • Ice Cap • Gyftrot • Doggo|
Dogamy and Dogaressa • Lesser Dog • Greater Dog • Jerry • Glyde
|Waterfall Enemies||Aaron • Moldbygg • Woshua • Temmie • Mad Dummy • Shyren|
|Hotland Enemies||Vulkin • Tsunderplane • Pyrope • Muffet • Royal Guards • So Sorry|
|CORE Enemies||Final Froggit • Whimsalot • Astigmatism • Madjick • Knight Knight|
|Amalgamates||Memoryhead • Endogeny • Reaper Bird • Lemon Bread • Snowdrake's Mother|
|Hard Mode-only enemies||Parsnik • Moldessa • Migospel|
|Vendors||Nice Cream Guy • Snowdin Shopkeeper • Gerson • Tem Shop • Bratty and Catty • Burgerpants|
|Other Characters|| NPCs • Monster Kid • Annoying Dog • River Person • Eight Humans • Asriel Dreemurr|
W. D. Gaster • Lost Souls