33-year-old Tasia Young agreed to have a THREESOME with her boyfriend last Saturday. And they brought another woman over to his apartment.
Then after they were done, her boyfriend got a cab for Tasia to take home, but he let the other woman STAY.
It's not clear if she stayed the night, or left later on. But Tasia responded by going back the next day, and setting his apartment on FIRE.
The building had extensive damage, but luckily no one was hurt.