I don't know why, but I've always had a feeling this question would be asked at some point.
For me, I've fallen in love with Aqua. I got into KH with the HD remixes and then bought the DS games to play. When I bought 2.5 and booted up BBS for the first time, I saw Aqua and thought to myself "She's a pretty girl." By the end of playing through Aqua's story, I had fallen in love with her.
She's a strong woman who has been through a heck of a lot, and she was never the classic damsel in distress. Instead, she fought. I think that's what made me so attracted to her - her strength and willpower and courage. Plus, she's so hot and that is a contributing factor.
Not only did I fall in love with Aqua, she's my favourite character out of everyone. I'm in love with her and she's my favourite - bonus points XD.
To this day, I am still in love with her and I think I always will be. She's my screensaver and I can't wait to buy the 2.8 Play Arts Kai figure of her.
Dang, Aqua ish a really nice character to play as, but I don't think I'd ever be that emotional over her or the other characters. I must say, ish interesting seeing these posts about people's feelings towards kh characters. The most I've ever felt towards a kh character is Kairi being so much like me, I found that to be kinda weird... but nothing else.