Only the Ring Finger Knows(2001)

Sono Yubi dake ga Shitteiru

Not only is Yuichi the most mysterious, sought-after guy at school, he's got an excellent shot at getting into any prestigious University...and no one knows this better than his secret love, Wataru. But instead of a vacation break spent celebrating beneath the fragrant sway of summer blossoms, both boys must surrender to Yuichi's grueling study schedule. How can they possibly sweeten the deal? A bet that promises to take their young relationship to the next level is in the works, but Wataru complicates matters when the very ring that symbolizes their precious bond goes missing. Prying girls and wisecracking best friends only fuel the flames of gossip, and soon the small white lies that were only meant to protect the heart of Wataru's beloved become poison arrows. With the test and their relationship on the line, can the boys hold on long enough to survive the sticky meltdown of their longest summer?

(Source: DMP)

Volume 1: Only the Ring Finger Knows
Volume 2: The Left Hand Dreams of Him
Volume 3: The Ring Finger Falls Silent
Volume 4: The Ring Will Confess His Love
Volume 5: The Ring Finger Persists