Birdie's Links
Birdie considers Sweet Devil his best friend, and he enjoys spending time with her. He always wants to make sure she's OK, and is glad that she helps him with his work sometimes.
Sweet Devil is confused about the feelings she has for Birdie, though he tells her it's called "Friendship". This is because she's never actually had a proper friend before. She does enjoy being with him, and is happy that he does as well, though she isn't sure how he'd react if he finds out about her powers.