Ianto gasps as the lube hits his skin like ice. He knows Jack is trying to be gentle with his fingers as he works one and then the next in but he can't help but whimper in discomfort as they press inside. He focuses on the words he's saying, on trying to actually breathe instead of just sob for air. Jack's always had a way with words at times like this, and he thinks what really does it is the way he so clearly means what he says. It helps him relax his body enough to let those fingers do their work and soon he's impatient for more.
"I'm ready, Jack, please!" He's the only one whose ever been able to make him beg like this.