DVEH-011 Fucking my sister's best friend

An older brother is said to be alone with his sister from the same school - Sumire. Taking advantage of her parents' absence, Sumire undressed and wandered around the house in baggy clothes. You can see erect nipples without a bra, and hairs are visible from the shorts. My brother, who was craving such unconscious temptation, devoured the body of the sleeping Sumire, and even remembered the jealousy to go on a date, until he forced him must say one sentence. What was the answer my sister gave to my brother who couldn't be honest with himself?