This page just submits to the Be* forum login URL and forwards you to the topic once logged in!
If you are worried (or cautious, as you always should be when submitting personal information on the internet) you can view the source of the page to verify where this information is sent.

Username:
Password:
Log me on automatically each visit: [does not work :(]
Take me to:
Paste a topic URL here or use ?destination=https://avatar.bethere.co.uk/forum/viewtopic.php?t=20246 or so in the address bar

See here for other tricks with the forum