https://www.pixiv.net/user/32890935/series/93593

Student yuri. You can read them separately, but they are somewhat tied together.

1. Senpai and Kouhai (後輩と先輩)
2. That Girl at Cram School (塾のあの子)
3. A Hopeless Romantic Wants to Give Up on Love (恋をやめたい恋愛体質)
4. A Friend's Love (友人の恋)
5. Cheating and Atonement (浮気と償い)
6. The Day I Realized (気付いてしまった日)
7. 500 Times Over (500回繰り返す)

"The Day I Realized" is a direct prequel to "Senpai and Kouhai".

"500 Times Over" is a direct sequel to "That Girl at Cram School".