(๑•ㅂ•)و✧ IKR
My exact thought
His father could be Bi, Omni, Poly or Pan
Probs bi if he really loved his wife because it's usually gay bi or curious/flexible in a lot of comics, but basically, not straight lol
but there's also a chance of a tragic story where his dad must've sacrificed his relationship with his highschool sweetheart (the teacher) bc of... ugh society or parents or just for the sake of being filial and marries a woman, has a kid.. you know, living the "normal" life... and then one day, he has a chance encounter with him.. past feelings arise and they finally reunite after all these years *yeets out tears*
....... or he could have found a new lover in xiao yu's teacher during a parent-teacher's meeting and discovers feelings that he's never felt before *cherry blossom petals dance in the background*
watch xiao yu's dad be gay as well *evil giggle*