We can say… he is some kind of dumb.

Once when you we're working in your room on computer, you heared breaking glass coming from the kitchen. You rushed there, knowing that Jisun was doing something there, and then you saw it. Broke glass on floor with a FAILED cake that looked like a damn magma (it was boiling) and your boyfriend standing by the side with burned and red hands, and teary eyes as he looked at the floor