Smile is a file-given name for a recurring black-haired NPC that appears at several points in .flow as of v0.1.
He appears in a room with another black-haired NPC known as Sister where he will laugh if Sabitsuki attempts to hit him with the iron pipe. Finally, he appears in the basement of the Corrupted School where he will attack Sabitsuki upon her entering the room while laughing manically.
Not much is known about him other than the fact that he looks similar to -and has identical hair to- Sabitsuki and Rust, apart from it being black. He appears in a room in the school with several children where he smiles if Sabitsuki takes out her iron pipe. He appears on the roof of the school where Sabitsuki will get the tattoo effect upon interacting with him.
- When you hit Smile with the pipe he actually speaks. He also laughs and you can hear the Kaibutsu giggle as well.
- As of version .15 you can now kill Smile during Rust's version of the Corrupted School event, as previously he was the only unkillable NPC apart from the Kaibutsu.
- Smile is the only significant boy in .flow other than Doctor Ochki.
- Smile is the only significant boy in .flow.
- There is speculation that smile and Sister are related to Sabitsuki in some way, either by blood or relation in that they possibly shared the same illness.
- Another theory is that Smile was one of her friends who she might have grown up with. Sabitsuki trusted Smile who betrayed her trust as they grew up. The fact that he's surrounded by school children could indicate that he became popular and perhaps eventually snubbed Sabitsuki altogether.
- Smile is very protective about Sister as pulling out your pipe will lead to him pulling out his weapon as if protecting her as she hides behind him. Perhaps his protectiveness of his sister lead to him not being friends with Sabitsuki anymore because he didn't want her hanging around his sister with Sabitsuki's disease getting progressively worse.
- A possible theory may be that Sabitsuki and Smile have done something wrong together. This could possibly explain the "Black Hood" and "Iron Pipe" effects. Smile also, of course, smiles when you hit him, possibly reminiscing on the act they performed. This could also explain why the Kaibutsu are so bloody and explain why Smile is in one of the school rooms alone with his hammer, as all the children flee from him. When he fights back during the corrupted school event, it could be an act of betrayal, for many unknown reasons. Sister seems to be afraid of Sabitsuki, possibly explaining this further.
- Sabitsuki and Smile may have been part of a gang dedicated to keeping the diseased from harming the healthy. The plus (+) designs over the eyes may have been a form of uniform. Smiling and giggling may actually be an early symptom of the disease progressing in Smile, or the fact that he may have been driven insane fighting the diseased and adapted their mannerisms. The corrupted school event may be a memory of how Smile was driven to abandon Sabitsuki and betray her due to the disease affecting her too far. She also didn't fit in with the diseased due to actively fighting against them in the past, which would explain why so many are her enemies yet have no apparent problems with each other, since they often appear in groups. Alternatively, Smile may have been protecting Sabistuki by knocking her out with the pipe before her pursuers could do any real damage to her.