18-year-old stepsister had sex with her stepbrother

The stepsister had a breakup with her boyfriend, due to which she was very sad. A few days ago, his stepbrother also had a breakup with his girlfriend and he was also very sad. Both of them are sitting and talking one day and in the same talks, both of them decide that from today we will fulfill each other's needs, we will not allow anyone else to come into our life and then both of them have sex.