Logged into another account without using a password

[Tee]

I just attempted to log onto Hypercities through my gmail account, however Hypercities logged me automatically on in another student's account. A student who resides in Fairfax (????) I did not use a password, nor do I know this student in Fairfax. After the random log on happened, I alerted the Hypercity founder about this concern, but this might be a more appropriate forum to address the security necessity. (I logged out of that account since then to respect this person's privacy) Thanks, t