My sister, who came to Tokyo, will stay in my room for a while. When I lent her a shirt to change into, she wore it like a shirt! Seeing her so defenseless and erotic in that outfit for days on end made me hard as a rock! She found out and it's awkward... but instead of getting angry, she suggested a dry run, saying 'It's okay if you don't insert it absolutely.' But gradually, it became a state of explosive wetness! 'We're siblings, so we can't do anything erotic... It's just a promise for a dry run,' she said, but with a squishy, wet pussy, I inserted it and came inside!