Face pressed into her, his tongue slipping deeper, a breathy moan escapes Celestia as her focus slips, eyelids fluttering. The rampant thought of being caught, the taboo feeling of the situation, and moral worry of what was happening... all culminated to play with her feelings, while waves of pleasure slammed against them, shattering her reason. They'd never gone quite this far before -- and certainly not even close when they had guards stationed right outside the door.