Most parts of Tsukishima were completely rough around the edges. He was annoyingly sarcastic, and didn't care much about most people's feelings. He was beyond terrible with communication, and seemed to spend ninety percent of his life with headphones over his ears, blocking out the world. Yamaguchi liked these parts of Tsukishima, they were what made Tsukishima, well, Tsukishima, but it was the softer parts of his personality that Yamaguchi loved the most.
He loved how Tsukishima would let him curl up in his side on the way home after a match,and the feeling of Tsukishima gently running his fingers through his hair as he dozed off. He loved the stupid pranks they would pull on Kageyama and Hinata, like the one time they talked in only morse code to convince the two that they could read each other's minds.
Yamaguchi loved that when he ran up to Tsukishima, he would almost instantly slide his headphones off of his head and down to rest around his neck, and the way his lips curved upwards just slightly in the Tsukishima version of a smile.
He loved how when he was feeling too anxious or depressed to even summon the energy to get out of bed, Tsukishima would stop by, skip practice, and even class if he needed to, to stay with him until he felt better. He would sit on the floor next to Yamaguchi's bed, his forearms and chin resting on the edge, and just be there.
Eventually he would end up inviting Tsukishima into his bed with him, and they would lay there, crammed onto the small twin-sized mattress that was really not meant for two people, under the mass of blankets, Yamaguchi curled up in Tsukishima's arms.
After a while, those days where Yamaguchi felt too terrible to move began fading away, and those moments of closeness with Tsukishima began becoming less and less frequent, and Yamaguchi missed it. A large proportion of the things he loved began fading away.
Until he was met with a surprise confession from Tsukishima, hastily whispered into his lips in a locked bathroom stall after a volleyball match. He welcomed it gratefully, and the closeness quickly multiplied by tenfold.
As their relationship grew into something new, something special, Yamaguchi was met with a plethora of new things he loved about Tsukishima. He loved the way his face went slightly red whenever he discreetly slipped his hand into Yamaguchi's as they walked together, or whenever doing anything that would be considered sappy or romantic in the slightest.
He loved the soft, slow, sweet kisses that always came late at night, when they were sure everyone in the house was sound asleep, taking time to just enjoy the presence of the other. Then there was the complete opposite of those kisses, the rough, sloppy, rushed ones, shared in the darkness of locked storage closets and empty bathrooms, hasty whispers against each other's lips of telling the other to quiet down, so they wouldn't get caught.
Yamaguchi wasn't quite sure what exactly had led to him loving Tsukishima and everything about him as much as he did, but if he was sure of any one thing in his life, it was that it was that he loved his imperfect, rough around the edges, completely amazing boyfriend.