EDIT: student pred ligeska CAN eat Satie. Tried it again after Ghost provided numbers =)
I've tested trying to get pred students to eat me too, only seems to happen if you're the student. I've even tried as Satie (the next biggest after a student) with Ligeska (highest stomach capacity).
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not a requirement i've definitely seen student ligeska eat student satie while i hadn't unlocked satie I think this was while I was a student wondering if they would eat me only for ligeska to snarf up the gyaru, if no standard students and apples are available other smaller preds are on the menu....but now the numbers are available...a student bella in theory can eat ligeska but ironically ligeska can't eat bella