DLSite:

1 - hoohttp://www.dlsite.com/books/work/=/product_id/BJ01277699.html
2 - hoohttp://www.dlsite.com/books/work/=/product_id/BJ01277700.html
3 - hoohttp://www.dlsite.com/books/work/=/product_id/BJ01291878.html

Base +22

Nice manga

Base +5

>The two are still too shy to kiss each other.
>On a night when she wanted to get closer to him during a school trip, she was having a good time with her boyfriend and his friends in the girls' room when a teacher on patrol arrived.
>As soon as they get under the covers, her 'boyfriend', who was hiding under the covers with her, starts touching her!
>The aggressive 'boyfriend' doesn't stop, flicking Chisa's erect nipples with his fingertips and playing with her sensitive pussy... Chisa lets out a sweet sigh as she experiences pleasure for the first time, but it's her boyfriend's best friend Keita!
>Chisa tries to resist, but Keita inserts his meat stick into her wet pussy...!

Base +14