Wiktionary
viscously
adv. In a viscous manner.
Usage examples of "viscously".
Her finger probed carefully around the red sensitive opening, the tips becoming moist from the white sticky liquid that oozed viscously from it, wetting the split of her buttocks and the bed beneath Had Kevin really been here?
The eye steamed, then exploded, its liquid humors gushing out and running viscously down the side of the head.