Kimi ga Kawaru Tame no Susume

To avoid burdening her family, our heroine starts a part-time job while studying at university.
She hears from her mother that her younger brother is dropping out of school and is without work, and then... "I'm so sorry but I will be reducing your allowance. I hope you understand..."

A sudden, unexpected supply line disruption... With her already small allowance reduced even further, she's at a loss at to what to do. This is when Tomatsu, a university faculty member, approaches her.
"I was wondering if you would mind helping some students lose weight?"
The chance to have her food expenses paid for in exchange for the part-time work is a dream opportunity, so she accepts the proposal right away. However, it seems the dieters in question will present formibable challenges:
A student studying literature who received a complaint for breaking a library chair after sitting on it...
A student athlete at risk of needing to repeat a year because he put on weight...

On top of that, could it be that each of the boys she meets on the job—Tomatsu, Akutagawa and Takuto—all have their own problems too...?
What will she learn about the boys' pasts and the problems they currently face...?