I don’t think it is a different person or a flash back but instead it is the same person. Since the white dragon and his reincarnated mate have more of a business relationship with the white dragon paying for sex, his partner just assumed he was brought to him for the purpose of sex and started stripping while sitting on the bed. I don’t believe either of them truly realize there feelings for each other (they both probably believe the other is only interested in monetary or metaphorical gain so they don’t want to express their true feelings for each other so that they don’t get hurt).
Wait is the white dragon having sex with another person? Or it’s a different person cuz if he is, I hate him (︶︿︶)=凸