Hajimete Datteba!

From FairGame:

There is first time at everything, and you don’t know anything about it. Not about your partner, not about yourself and even how to advance in love. In a certain port city, energetic high schooler Kana, and firm high schooler Kouki live. Two of them experiencing first time at every thing they do. Author of “Smash!”, Saki Kaori presents, Hajimete Datte ba!. A heartful love story has now begun