AMINE AND MANGA

Only the Ring Finger Knows (その指だけが知っている, Sono Yubi Dake ga Shitte Iru^?) is the title of a shōnen-ai light novel series written by Satoru Kannagi. It was made into a manga illustrated by Hotaru Odagiri, which has been licensed in the United States by Digital Manga Publishing.
In the school that Wataru Fujii goes to, when one wears matching rings on their right ring finger it is a sign of friendship, a ring on the right middle finger means single, and to wear matching rings on the left ring finger means a couple. One day Wataru accidentally switches rings with the very kind, handsome, popular senior, Yuichi Kazuki, because for some strange twist, their rings match. After the strange encounter, Yuichi is uncharacteristically mean to Wataru. Is it because he just can't stand him or is it because he actually loves him