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Tear Jerker: Baka and Test: Summon the Beasts
In Episode 4, Minami spends the whole episode trying to get Yoshii to eat lunch with her, but is prevented from doing so due to several inconveniences. When she finally has a chance, she fails to invite him and botches it for herself. She is then seen eating lunch alone on the rooftop and mutters a weak "idiot..."