I'm looking for a manga that I've read before but I forgot what it was called it was about 2 years ago. The scene I remember was it was school life, but then 'they' (couple) had sex in front of the school or lots of people but I think it was a sport carnival or something

PLEASE HELP ME FIND THIS MANGA!!!

also is there a manga that is about a shopkeeper that sells guns/pistols to people and one of the customers starts getting intimate with the shopkeeper to the point where a gun is thrust in and out of him>?

Oshioki Gakuen?

thanks so much!