Yacchimonee
Complete | fuwa shinri | 2015 released
It's really good if you read it as a coming-of-age, slice-of-life book. I noticed Kiichi was coded as bisexual when he was musing on the confession from his best friend, so it was nice to see it reaffirmed later when he makes a distinction of his first relationship (not having had a boyfriend or girlfriend).
Bokura ga Koi wo Ushinau Riyuu