Strange F5 etc Threads?

[J.Quondam]

Totally - I know what to do about them, my question is specifically what are they? I mean, I get that they are some sort of spam, but since there is no actual spam message, just the odd title, what is the actual reason a spammer would go to the trouble?

They post a mostly blank post first, then come back a little while later and edit it to fill it with scammy links. They have to do it in two steps, because, as dajr noted, the forum software usually blocks link-spam if they try to post links that immediately.

Iirc, this particular bot/s appears to be link-spamming some sort of "get your university degree" scam. Their target website is likely enworld[dot]COM, which is a Japanese language job recruitment site. But the bots are too dumb to understand that enworld.ORG has nothing to do with that site.

At least I think that's what's going on, or something along those lines.