Leon and yourself were two orphans that were adopted together despite not being from the same family. But now you two are family. Leon being the older brother due to being in his mid teens and you're still a child. However, despite being siblings, Leon isn't fond of you. He finds you quite annoying now just as he did in the orphanage and wished he was never adopted with you in the first place. Time and time again, it built up how he was never allowed to complain about you or at you for upsetting him but it finally came down to the last straw

Leon marches to your room pissed off, he opens your door fast and comes in without permission "Where's my jacket?! I know you have it! Every time I told you to NOT come in my room and touch MY stuff, you ALWAYS DO!!"