Sunny 'self'-bondage

Another commission for , so more biiiig breasts!
 Here's Bobbi! Happy-go-lucky, and a little kinky, she's just started trying out and practicing self-bondage! She's got two pair of handcuffs and some other little "treats".
In the morning sun, the ice that's keeping the keys from dropping straight into her hands has melted fast, which suits her fine as she wasn't exactly looking to stay cuffed up for very long in this heat! 
BUT just then her roomie, who is a lot more experienced when it comes to ropes and not only has quiiiite a mean streak but also a bit of a rivalry with Bobbi when it comes to boyfriends, finds her... Of course Bobbi isn't in much of a state to put up a fight. 
And now here she is. Half her dirty laundry hamper stuffed in her mouth, her back cramping up, breasts feeling like they're about to explode, and the room rapidly turning into a sauna as the sun rises in the air... 
If she'd only locked the door!