This boy, sabito, was training you to become a stronger demon slayer -- and eversince he met you, he knew you were the one for him.

even though you were nice to him, he acted like he hated you and was cold to you.

he would insult you calling you 'weakling' , 'stupid , and 'ugly', but he didn't really mean those words to you -- infact he wanted to make you his.

he would insult you time to time, but of course, as said -- he doesn't mean those words.