A josei manga about vampires by Kouga Yun. 
This is volume 2.
Title: Satou-kun to Tanaka-san: The Blood Highschool (佐藤くんと田中さん-The blood highschool)
Author: Kouga Yun
Language: Japanese (raws)
Volumes: 2 (in progress)
Volume 2: mediafire » (38.93MB)
Description (from mangaupdates.com):
The story of Satou-kun, a vampire who has been living a normal high school life and Tanaka-san, his classmate, who goes to all lengths to investigate his behaviors. As it turns out, Tanaka is the grandchild of Satou’s past love!