At first, Akari thinks Ryoga is just uncomfortable at the idea of being invited over for dinner. He takes the rice with a muttered thanks, carefully chews his fish… and gives Yuma brief glances across the table with a set jaw. Yuma returns the look with a smile before glancing at Akari next to him and back down at his food. She thinks perhaps Yuma is just trying to make Ryoga feel more at ease.
Except this behavior subsists throughout dinner. Haru doesn't seem to notice and Obomi is, of course, busy zooming around the living room dusting while reciting her daily reminders about how Yuma is terrible at everything. Ryoga gives quiet answers to Haru's questions. But occasionally, Yuma gives Ryoga a sly look that he quickly abandons when he thinks Akari is looking, and Ryoga's face gets pinker each time as he shoots a warning look back at the younger boy.
At the end of dinner, as Obomi clears the table and Haru gets up to make some tea, Akari spots Yuma's leg move slightly under the table. Ryoga's shoulders tense as he shakes his head slightly at Yuma and looks down at his lap, blushing once more, and Akari realizes what's going on. She waits until Haru sets the cup of tea in front of Ryoga, who mumbles his thanks without looking up. As he takes a small sip, Akari rubs her foot slowly and gently all the way up the inside of Ryoga's calf and relishes the way he sputters his tea back into the cup, the look of stunned disbelief mingled with horror creeping over his face, the way his hand almost drops the teacup on his lap.
"Need sugar, Shark?" Yuma asks, tilting his head curiously.
Ryoga's mouth opens and closes like a fish a few times and he shoots a frantic glance at Haru and Akari, who merely gaze at him, though Akari is having a hard time keeping a straight face.
"N-no…" He sets the cup back down. "It's just, um, hot."
When he thinks nobody else is looking, he mouths what looks like a death threat across the table at a puzzled Yuma and Akari has to excuse herself to keep from laughing.
It's so easy to toy with those two when they're flirting.