What happens when you switch accounts

Hi! Can you tell me what happens if i switch accounts in rekordbox? Me and my flat mate bought a ddj400 recently and we were planning to share it, we've read that you can use the license key on two computers, but we didn't know that it has to be the same acoount... We already have our separate accounts from before, so I was wondering what happens with my music and playlists if I log out of my account and log in into his account?

thanks