guy i just want an answer whom he likes he friend or teacher ???

Setagawa likes Kousuke ( the teacher / older brother ) in a romantic way.
He considers Kensuke ( the best friend / little brother ) like his little brother or his son. So it's more of a protective love for his family.

He says it here : http://www.mangago.zone/read-manga/hitorijime_boyfriend/uu/hitorijime-boyfriend-chapter-5.html/pg-24/ and http://www.mangago.zone/read-manga/hitorijime_boyfriend/uu/hitorijime-boyfriend-chapter-5.html/pg-25/

ok thx