Responses
Koi To Kaerou. Not 100% sure...
It's from the k-sensei series, there are 4 books, i think that page it's from the 2nd one
the first one is
https://www.mangago.zone/read-manga/k_sensei_no_yajuu_na_aijou/
https://www.mangago.zone/read-manga/ikumen_datte_koishimasu/mf/v01/c001/3/