Trill on Eden(2007)

Eden no Trill

Ritsu has had bad luck her whole life. Starting fresh in a new boarding school, she hopes to leave her problems behind, but fate crosses her path with that of the school's troubled musical genius, Eiri. Almost immediately, her bad luck explodes to an all-time high. Unfortunately for her, she's been selected to be his new roommate — and to turn him into a proper, well-behaved student before he's thrown out for good! Maki Fujita has created a number of fan favorites in the manga field, and Trill on Eden has all the ingredients of another smashing success — a tempestuous teenage romance, memorable characters, and a plot as up and down as a rollercoaster ride.

(Source: Go! Comi)