Been thinking about teenAtumu growing up in his shitty foster situation, where he usually eats an average of once every 1-3 days, situation dependent.
The only money he gets are when his foster dad gives him some cash to buy basic household shit and sometimes groceries to cook for the family.
A lot of times his foster parents will order food, so Atumu gets to use the groceries for himself. He can usually make the food last about a week if he eats once a day. But sometimes the parents expect food to be ready at home, which cuts into how many meals Atumu has for himself, so it has happened that he hasn't eaten for 2-3 days. It's not every week, but it's not too rare. He averages perhaps 5 meals a week.
When he is finally enrolled into public school at age 16/17, he realizes there is a dedicated time when everyone eats. He doesn't usually have the $2.50 for daily school lunches, but he can sometimes pack his precooked lunches.
At some point, Startop notices a day when he doesn't have a lunch, and Atumu lies (poorly) that he already ate. Startop shares his lunch with Atumu, but Atumu is fairly reluctant because he knows he can't afford to pay Star back.
It has happened several times that Startop packs an extra lunch for Atumu when he notices it's a frequent occurence that Atumu doesn't have food. Atumu is clearly starving, but keeps insisting against taking the food because all he can think of is how he can't afford to be indebted when he can't pay it off. Star lives in a communal housing with his sister and her many kids and roommates, so there's always food in the house. He doesn't manage his own finances, so he doesn't understand Atumu's panic.
Atumu did try to pay Star back at some point - with cash, which Startop thought was ridiculous. Then with a home cooked meal (at the expense, of course, of Atumu eating), which Star enjoyed but didn't understand. But Atumu knew he couldn't keep accepting Star's food because he couldn't maintain paying him back. Star really never understood this idea of "paying back" - he never expected it and he never asked for it. He tried insisting against it.
Finally, they found a good compromise with Star inviting Atumu back home with him. Startop would feed him dinner, and Atumu would help tutor him and help him finish his homework. This hardly felt fair for Atumu, since schoolwork is an absolute joy for him, and it felt like an uneven trade, but Startop was able to convince him. No one had spent the time to help explain the concepts at a pace and in a way that Startop could understand, like Atumu did.
Plus, Atumu spending after school evenings with Startop meant less time with his abusive parents, which would be both a good thing and a bad thing.
At some point, Star wanted to come over Atumu's house just to see how Atumu lives, and it's a huge point of stress for Atumu. He doesn't live in a great condition and he knows his foster parents, rarely sober, can be very unpredictable. The house is hardly fit for guests.
...that's a story for another time I guess
