Its not a stupid question at all! If tumblr’s tagging system weren’t awful I could direct you to the tag where I answered just this before but here- whump is the Pain fandom. People who like having characters (oc or not) go through painful situations. It can be for character development or for caretaking and comes in many, many forms.

And if you mean like, what it says about you as a person I really don’t think it means anything other than you like whump. Irl I instantly feel others pain and care a lot (so I don’t like live action whump stuff as much) but I do like reading/writing/seeing art of whump of my favorite fictional character.