Shojo-tan: Dai 1-maku Goshujin-sama ni Shojo o Sasageru Kenage na Maid Hen

Maid wants to establish true master-slave relations. For her dedicating virginity to her master is a proof of loyalty, a trial on the way to becoming a full-fledged maid. And the long-awaited day has come.

[From vndbreview]