The Bonus Room is an extra location accessible after the Good Ending if Lonely Girl decided to bring the Familiar Doll with her. If Lonely Girl also found the Hidden Pages, they will appear in the back of the room, where they can finally be read.
Temmie Chang, the game's creator, appears here. The room also has several notable objects from Lonely Girl's House: It has the TV from the living room, the radio and Familiar Doll from the kitchen, and the shoes from downstairs. There are also boxes that look the same as those in the basement, and the same kind of lamp that frequently appears in Lonely Girl's house.
The four pictures in the back of the room show Lonely Girl in the Other World post-story. She seems to be happy, but has apparently lost all memories of her parents.
The TV in the back of the room will play a movie that explains Lonely Girl's current situation, and shows her finding Yoki.
Speaking to Temmie will allow the player to ask several questions to her about the game's story, as well as delete her from the room. She refers to the player as "[insert player name here]", likely as a joke about games that data-mine the player's computer to display their username or real name without it being entered.
The questions that may be asked to Temmie include the following:
|Who are you..?||"I'm Temmie! The creator of this game!!!! I draw, illustrate, pixel, animate, write now I guess. I made sound effects (in-game) using a cute program. Behold!!!!! / Please hire me i need work."|
|Why am I a cat?||"Haven't you always been?"|
|What happened to the lonely girl..?||"It's probably confusing right... / She stepped into a new world, however because she was influenced from abnormalities from her decaying world, she was shifted into a demon. / This is partially a premise for the game I want to make next....... / But that game is much more ambitious and I don't know how long it will take me. / I hope you get to see it some day soon! / Anyway.... I think she prefers being this way anyway. It really is a "new start" for her. / Also.. It's very similar to what she always wished to be anyway. It works out!! Kind of."|
|Who is that handsome demon man...||Think of him as an anti-hero. / ... / Sort of... / ...But he's not really a good person. / I guess in this story he's ok.|
|His character design..||"Yes what about it"|
|..Did he need to be a handsome demon man?||"Yes"|
|"Who are the characters he's referring to?||The someone he wants to return to is Yoki. / She'll be the main character of the game I want to make soon. / The character causing everything... / You'll find out in the one day I ever finish that game. / (I hope I do)"|
|"Is this... all there really is to this game?||That's it!!!!!!! / ... / I'm sorry...there's so little... / This was just meant to be a test game I made to learn how rpgmaker works so I could make the game I actually want to make. / ....I hope you enjoyed it anyway!! I ended up getting attached to her story and made it longer than I intended. / I felt really worried writing a story with this type of tone and themes.. / I really hope it doesn't upset you too much.. / I'm sorry if it did..."|
|You must be eliminated. Begone.||"...huh?" (Temmie disappears)|
This is the only part of the game where the player does not control the Lonely Girl. Instead, they take the form of a small, white cat. This might be in reference to Toby Fox's avatar of a small, white dog, or it could just be coincidence. There is also a ball of yarn that the player can push around the room.