[Rinvelt]

Spoiler:

She went away a day or two before the incident in vol 10, and a day or two pass after said incident, then going to the kingdom takes time because they all went together here, so Rio can't just fly.

iirc, Reis noticed Rio and decided to greet him because he's interested in him. Disclosing his identity was just to rile him up.

Note that I might be wrong for the timeline because I speed read them, so not recalling clearly the details.