Simgirls VN - HOW TO DATE?
The feature will only be unlocked after reaching a certain gradol level. Once it is unlocked, go to the person you want to date (main characters only), click the little icon (or use shortcut key) right besides Tomoko's head at the lower right corner, and BOOM, your date's head will stick to yours, indicating that you've got a company.

Play the game now: 
https://www.newgrounds.com/portal/view/706364