This is from a yuri doujinshi called Chocolate Melencholy, and it's freakin' hilarious!
Basically, it's about a flat-chested little girl named Choco who has a crush on some guy in her class. She planned to give him a love letter, but due to her nervousness, she accidentally gives it to the blonde, busty chick named Remi. Remi is rather popular girl in the school so her supporters yelled at Choco for such "perverted" things. After they went away, Choco realized Remi took the letter so Choco decided to pay a visit to her place to get it back. Little did she know that Remi actually has a crush on Choco (hell, check out her room ) and thought the love letter was for herself. Remi then gave Choco her "affections" and hijinks ensues!
"If you're not cheating, you're not trying!" - R.I.P. Eddie Guerrero (1967 - 2005)
Through tragedy, she found triumph. R.I.P. Coretta Scott King (1927 - 2006)
Long live the "King of Pop"! R.I.P. Michael Jackson (1958 - 2009)
"If you're not cheating, you're not trying!" - R.I.P. Eddie Guerrero (1967 - 2005)
Through tragedy, she found triumph. R.I.P. Coretta Scott King (1927 - 2006)
Long live the "King of Pop"! R.I.P. Michael Jackson (1958 - 2009)