Uya

A sporty girl who always looks on the bright side.
Uya used to live with their parents until, craving freedom and her Onii-chan, she moved into the protagonist's house together with Saya.
She hates studying and isn't doing so well at school, but she loves her Onii-chan like a good little puppy!
Likes to be out of the house, and can often be found nuzzling up to Onii-chan with a big grin on her face. You can practically see her tail wagging.
Sometimes tries to find opportunities to keep him to herself by taking advantage of Saya's shut-in ways. Ruled by her emotions, she likes to be active and is prone to physical expressions (attacks) of love.
Has a super sensitive tongue, to the point that she can identify the individual ingredients in a meal. Really can't handle spicy or sour things, but sweet stuff is A-okay.
Black coffe will knock her right out.
Basically, she's kind of an airhead.

"I'm practicing basketball in place of studying! You saw how hard I worked today, right?"