Well first, thanks for coming forward and presenting your work. Second, it would be good to put more detail into the people. All you really drew was the outline of the people, and theres nothing filling them. Its almost like empty space. But don't worry, alot of beginners make this mistake.
As for the situation, well, I really don't care for genital tickling or bondage for the purpose of genital/sexual tickling, as it can be vulgar in nature.
I agree with skwrlbait. Perhaps a foot tickling picture would be better suited next time, and it will give you the opportunity to put more detail into it that way.
Overall though, its a good start. Keep at it. 🙂
- Damien