Nathan couldn't really parse what he'd just seen.
He had been trying to peep at Tim through the tent opening when he lost his balance and bumped against the tent. Quickly dashing toward some nearby bushes, he only barely wasn't caught by the strapping intern. What he wasn't ready for was for Tim to decide to randomly (and shirtlessly) start wandering through the archeological site they were about to start investigating.
Then he saw the big oaf kneel down and drink from a wellspring in the middle of the ruins, flex a little bit by the water and return to the camp. The weirdest thing was, it had almost looked like the wall behind the spring had filled with images as soon as Tim left, but when he tried to get closer they vanished again. Trick of the light?
Nathan looked around at the pottery shards and even some partially unharmed urns and decided he'd come back here first thing in the morning, when he could actually see anything and the darkness wasn't playing weird tricks with his perception.
The Greek Cultural expert looked at the small pool of water in confusion. This wasn't usual of greek fountains, the greek usually built the pools and wells they used for whichever reason, and this was just a hole in the ground with water in it, completely unmodified by whoever inhabited it in the past. Even so, it had walls built around it, and the floor tiles seem to have been deliberately set around the pool, so it couldn't have formed after this building was already here... Could it have been a temple to Achelous? Maybe one of the other potamoi?
Nathan felt his gaze linger on the clear waters. Even under just the moonlight he could see several feet into the water and yet could see no sign of its bottom. He knelt by the pool, what could have overtaken Tim to drink from this, knowing too well the risks he would incur?
He dipped his right hand into the waters, the water was cold against his skin. He cupped a bit on his palm and brought it close to his face. It smelled fresh, like a cool breeze in a hot summer day. He brought his face closer. "Just a taste, for science." He told himself as he brought
his hands to his lips and sipped. It tasted... It tasted like...
"Like water from a hole in the ground I just found." He snapped back from whatever had possessed him to drink from this spring. Shaking his head and drying his hands on his clothes. "What is IN this water? Was this what Tim felt when he got closer?" Nathan quickly emptied his canteen on the floor and dipped it into the pool. "You are going to the lab for analy- Ooh." He moaned as he felt a shiver go through him.
He felt his body slightly spasming under his clothes, his muscles contracting and releasing rythmically for a few seconds. A tingle ran from his scalp down to his feet, lingering slightly longer when passing his nipples and his crotch. As soon as it had started, it was over. Quickly examining himself under the dim light of the moon, Nathan couldn't see anything different.
"Whew- Okay, you're DEFINITELY going back to the lab." He said to the canteen as he screwed the lid shut and placed it back onto his belt. He felt his nipples hardening in the cool night breeze, his slightly tighter shirt brushing against them, sending pleasurable feelings straight to his dick. Maybe watching Tim flex shirtless in the moonlight had made him hornier than he had realised, he thought, as he got into his tent. "Can't wait to see those ruins during the day."