The bj was so unnecessary…

Reaaally out of place. A complete tonal shift, actually

i feel like this was the work of some editor because they often push authors to rush their plot and add sexual stuff in BL

Yeah, it's probably the Editor, cause some do push the mangaka to take another route to test the water. Sometimes it's great, or other times not so much. Then when the mangaka is popular or is completely done everything they later complain about the Editor's decisions.