k-on!, tainaka ritsu, tainaka satoshi, nounanka (abubu), 1boy, 1girl, blush, bra, breast grab, breasts, brother and sister, brown eyes, brown hair, female, groping, hands under clothes, hands under shirt, hetero, incest, lingerie, male, nervous, panchira, pantsu, school uniform, short hair, shota, siblings, siscon, skirt, skirt flip, straight shota, teenage girl and younger boy, tongue, underwear, upskirt, white panties, yellow eyes, translated