So in 閃の軌跡, the main character's name is リィン. I've seen this kind of thing before but I've never been able to get a good answer for how リィ is different from リ or リー. Even when the characters in the game say his name it's hard to hear any difference, but they're not saying it right after the リー. Is it just for style?

In Steins;Gate, まゆり calls herself まゆしぃ and I can't tell the difference between that and a regular しい. My guess is she uses ぃ just because it's cuter...

Edit: Wikipedia says 前の音がい段の音の場合は、長音と同じように扱う。