From the Super Mario Wiki
Hearts A-Flutter is a quest in Mario Party Advance that is assigned by Flutter, who is found on the Mushroom Condo's third floor. When the player visits Flutter, she gripes to them about her woes; hearing her out promptly starts the quest, while ignoring her causes her to complain further about the player's callousness.
Once the quest begins, Flutter explains that she has fallen in love with someone, but she has never talked to him face-to-face and does not know his name. She asks the player to relay her feelings to him, describing him as someone with a "big, blue eye." Her description refers to Mr. I: when he is visited, the player can either freak out about the giant eyeball floating in front of them (causing him to complain about the player making fun of him), or directly tell him about Flutter's feelings. He quickly rejects Flutter, since he barely knows her and he happens to already have his eye on someone else (which ties into his quest, Love That Princess!). Once Flutter hears the bad news, she becomes incredibly distressed, but still thanks the player for helping. The quest ends with her giving them the Love Me Not Gaddget and then asking them to leave her alone.
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