A tense air rose between Seth and Rias the tension actually coming from just Rias as she kept on staring at Seth and trying to process several thoughts while Seth just calmly sat looking at her.
Not even mentioning the ridiculousness of Seth wanting her to sit on his lap, Rias was still stumped over Seth's sudden generosity as he called it.
Though he had given her a simple and believable reason, she just couldn't accept that things would suddenly become so easy and Seth who had shed light on how aware he was about his value would offer her a share of his specialness without asking for something from her.
"If you thought something of your relationship with Roushi, then why did you try to get between my legs in the first place?"
"Correction I haven't tried getting between your legs, all I did was ask you to put your hands between your legs and play with your kitty, and as for why I did it, isn't it obvious?