I'd want to say Maria for her maturity and her 2p outfit but I have to say no because of her hair color. Only blonde and brunette couples should have matching hair color. Plus, she's a bit Shinji. Sophia is childlike now but she can grow out of that. Added to that is Fayt's "Are you unhappy with me, my princess?" line. It's not simply a bid to humor a naive girl's sense of romanticism but an easy indication to their true feelings.