Gakuen Club

Our heroine is entering her junior year of high school when she finds out she will be suddenly transferring to the famous Kirika Academy located in the city due to her father's new job.
She is quite excited about starting her new school life, but she stumbles upon a secret night club that is being operated after school hours, and gets herself roped into working the kitchen...

As she grows closer to the other waitstaff of the night club, she learns of their past, and finds herself becoming more and more involved in a complicated web of human relationships and romance...

[From Steam]