Fuuka doesn't know Raidou all that well but she does trust him. The first time they actually talked, I believe it during an art show? She was a little worried if he was able to keep his promise but so far? He has and that make Fuuka trust him.

Admittedly, before Fuuka actually had a chance to talk to him, she did feel a little bit awkward. She was thankful to the previous Raidou for giving her a position in the agency and had an overall good relationship. To find that she had to start over again? Yup, awkward tiems be ahead. However, she thought that he couldn't be that much different regardless.

She does wish that she could talk to him more outside from a friend of a friend!