Can Isabella hold out?

No, But She Has

That Slave4U is some powerful stuff. Emma torments Isabella for a good hour, but she is unable to cum without permission, so she is in agony.

"What's the matter, Dumbfuck, do you want to cum?".
"Yes, Mistress.".
"You'll just have to wait.".

Mistress fists Dumbfuck's pussy over & over, occasionally brushing lightly against her clit. But her pussy stays dry because she hasn't received the command. You watch intently, Emma always surprising you.

"Cum, Dumbfuck.", Mistress commands & slaps her cunt.

Some juice starts spraying out, but Mistress doesn't let lt last more than one second.

"That's enough, Dumbfuck. Put this vibrator up deep.".

She gives Dumbfuck a thick, long black vibrator on a high setting & Dumbfuck inserts lt deep into her hole.

"Make sure you get the clit.".

Dumbfuck starts wriggling around & breathlessly gasping & moaning, her eyes rolling back. She really wants to cum now, but she dare not ask. Mistress continues playing with her, only letting her cum a tiny bit at a time, untill she feels that Dumbfuck has been adequately trained. You're just amazed at how sexy your girlfriend is & how much her sex **** can take without cumming. You can't sit back & watch any longer, you need to fuck them both right now.