My Stepbrother Convinces Me to Skip the Gym and Have Fun with Him Instead!

I was ready to go to the gym, you know this perfect body is not something easy! I work out a lot and it makes me feel better in many ways, not just physically... but maybe there's only one thing I like more: sex! and my stupid stepbrother knows it so he used my weakness against me and convinced me to stay at home and fuck instead of going to the gym!