The first time Fuuta disappeared after they'd sort of started going out, Gokudera felt a sudden sense of disappointment. No- it wasn't disappointment, that was a rather mild word to describe the stab he felt. But that was Fuuta's nature, so he could only get up to face the noon sun alone.
The first day wasn't too bad, actually. He went out to visit the Tenth after lunch, just to see everything was alright, and to hang out for a little while. Then he went over to the marketplace to explore the stalls; they had new wares on sale every so often, and while strolling down the narrow dirt aisles, he saw a native amulet that was supposed to be for chasing away illnesses. Gokudera didn't really believe in this kind of crap usually, but when the goddess herself appeared to the people on occasion, you had to put some sort of stock in it, right? So he got it, and spent the next hour wandering around before he went back to get ready for work.
But as the days dragged on, Gokudera gradually got more moody. Waking up in the late mornings with the house empty generally brought a frown to his face, and he absorbed himself in his usually preferred solitary activities, visiting the Tenth aside. Still, there was only so much dynamite he had here, and the literature on the island sucked ass. He started charting out calculations to the most ridiculous things he could think off, most of which had their roots in Fuuta's rankings.
On the ninth day, Gokudera went to the Mao he Xue, the collar starting to tighten around his neck. But as he started unbuttoning his shirt, he found himself pausing, and his lips forming Fuuta's name in silence.
Two weeks went by in this manner. Gokudera found himself worrying, and keeping the amulet close to him, somehow thinking that perhaps it could work by proxy. Was the idiot running out of pills? Had something happened? The futile messages he sent were not returned, so he could take relief in the fact, that, at least, Fuuta had not returned home, selfish as that desire was.
On the sixteenth day, Gokudera was awakened by something burrowing into his bed, and he started to protest sleepily. The growl died in his throat though, at the familiar brown hair. He was back. Gokudera sighed, and sank back into the bed, wrapping his arms around him.
"You forgot to leave a note before, you idiot," he said, quietly. "And stop tracking dirt into my bed." He could have sworn he heard a chuckle then, and he smiled in response. The dirt didn't matter actually, it could be cleaned up later. What mattered was that Fuuta was back.