Have mercy! My dick is going to fall off!

Maeno Shun is an indecisive high school students. His parents have to leave for an appointment overseas, leaving Shun behind. They arrange for two of his cousins to look after him in their absence.

One cousin is Madoka, a cheerful, mischievous girl who teases Shun by showing him her sexual allure.
The other cousin is Hikari. She is kind and familial oriented, taking care of things as a new wife would.
The sisters both had their eye on Shun ever since they were kids, and now that they have been reunited with him in this fashion, they start fighting over him!
The sisters compete in terms of cooking and looking over the sick, eventually moving on to a more sexual contest!