Oba Netori -Otto no Shiranai Midarana Kankei | 叔母寝取り ～夫の知らない淫らな関係～

Rieko Momose the protagonist's aunt. Tender and matronly, like a true mother always doting on him. She's fond of him but never thought of him "that way". Her relationship with her husband is healthy. They have a daughter. She's also incredibly sensual, giving off vibes that attract other men... while her husband seems blissfully ignorant of her needs.