Page 8: She says "I'm out of your league." which implies she believes she is too far above him in looks or status for him to realistically pursue, but her other statements and actions show the reverse. She should probably be saying "You're out of my league."
Also, with Ria's side eye when Yohji and Mirea met in page 13 of last chapter, I was certain Ria had figured out that Mirea had a crush on him. Her lack of reaction to "I already took care of [Mirea's repayment]." doesn't show that. She's usually much more jealous and suspicious. Maybe she doesn't think of Mirea as a threat due to her age.