Prequel/ spin off of Gosan no Heart - includes the doujin
It’s so lewd. All of this authors work is so sensual and lewd especially the smut even where there isn’t a lot of explicit smut. Really liked this couple, the brother may seem like a jerk and fuckboi piece of shit, he kind of is but at the same time wholesome and just really insecure.
Next in the series is Yamanai Fukou no Owara Sekata ( I think)
sequel to the orginal Gosan de Fukou na Koibanashi is kinda a compilation of all the extras plus a bit more from both the couples
Owaranai Fukou Ni Tsuite No Hanashi