Pic not really related. A boy hears rumors of this girl (who he likes) is a slut, and is screwing around at school. He makes his move on her, they fuck, and she says that she's not really a slut and she was a virgin.
It's translated in English. Style reminds me most of Seto Yuki or Maruta, but it's not them as far as I can see.
I did a lot of searching on the panda with the relevant tags.
That's all I have to go on. Any help please?
It is indeed by Maruta.
http://exhentai.org/g/321564/708adb4b71/