Constellations in My Palm (Yaoi) by Chisako Sakuragi
Enji is moving on to college and it turns out he'll be living with his cousin Misuho, who he hasn't seen in seven years. Enji, once the younger cousin that Mizuho thought of as a cute little brother, is now a tall, handsome man practically oozing with cool. And yet, despite how close they used to be, Enji's giving him the cold shoulder. Has Enji simply grown out of being Mizuho's surrogate younger brother, or is he trying to hide his trun feelings?