Onegai, Ikasete!

Teased to the brink, forced to beg.. I'm so embarrassed, yet for some reason I obey.. Am I an extreme masochist?! I'm working as a home tutor for my boyfriend's younger brother. My boyfriend's so busy that I can hardly see him, but I'm with his brother every day.. Yes.. I.. I'm cheating on my boyfriend with his brother.. My boyfriend's cool and composed, and his brother is a mischief-maker. They're completely different from one another.. but the one thing they both have in common is that they're both dominant and love to tease me!.