Board Thread:General Discussion/@comment-28211557-20160310122940/@comment-30501299-20161215214134

the game provides plenty of hints and evidence of laughter being a coping mechanism for pain and sadness this includes Sas making jokes and smiling all the time despite how sad he is from the resets and his nihilism, Snowdrakes dad mentions it, the orange and green monster near Grillby's talk about how they all laugh and tell jokes to mask their pain because they can't do anything and Toriel laughing when she dies or when you leave her. also Asriel says she went down the mountain for a not very happy reason, when describing the ribbon Chara says if you are cute monsters won't hit you as hard, which heavily emplies she was abused and the house has benn made safe so there is nothing sharp or for the fire to be able to burn which wouldn't be for preventing Chara from attacking them as she ended up with a knife in a box seemingly as a present for her, it was probably to prevent her from using these things on herself. Humans most likely abused her to the point of wanting suicide by falling down the deep hole in the mountain and they are the species that trapped all monsters inside the barrier so I can see where her hate comes from, not being the nicest person is because you are doing everything perfect with determination, just like how Monster Kid sees Undyne as a jerk after you save him, even though you know she would leap off the bridge to do the same.