[Yoshida Tobio] Otomezaurus ~Chikako~ (Part 1) [Lilporkins]

When a worried mother asks her daughter to look after her little brother, Chikako takes the request to heart in ways nobody intended—stripping out of her school uniform and offering her soft, big breasts for her shy little brother to touch, lick, and learn from. What starts as a mission to 'make him less stupid' melts into eager fondling, breathless nipple sucking, and a devoted promise to make him cum every single day. Part one of Yoshida Tobio's sibling romance follows a yandere sister's slide from dutiful helper into an insatiable lover who has no intention of ever letting her brother go.