Leo
Your eyes. Leo loves the way they sparkle whenever you watch Space Heroes with him. Your (e/ c) eyes seem to shimmer and glisten every time you laugh.
Raph
Your laugh. You may hate your laugh, but he loves it. Your laugh alone can brighten his day and calm his anger. Raph goes out of his way to make you laugh just so he can smile.
Donnie
Your hair. He loves how your (h/c) hair is so delicate and how you twist it when you're nervous. (Sorry if you don't do that. I do xD) Every once in a while, Donnie will braid your hair when you're sleep to watch your confusion when you wake.
Mikey
Your nose. As strange as it sounds Mikey loves your nose. When pokes your nose you often scrunch up your nose, which always brings a laugh from both of you.
Casey
Your blush. Casey tells you all the time that he likes your blush. It's the only thing that gives him hope that you might like him back.