Rumour #1- Mana & Gackt, were, like, GAY & stuff.
Erm, no. The hugs etc. were FANSERVICE. Don't know what that is? Look it up. Here's a handy link. Mana & Gackt have both stated qualities they look for in a woman. Gackt has also been married. Even if Mana & Gackt WERE gay/bisexual, would it change the music in any way? No.

Rumour #2- Mana & Gackt were gay then they broke up & that's why Gackt left the band.
>_< Just...no. See above. Even after Malice Mizer giving an official reason (creative differences) & Gackt dedicating a chapter to it in his biography, the reason he left is still unclear. However, it's clear that Mana & Gackt haven't communicated in a long time...

Rumour #3- Mana is a bitch; he kicked Tetsu & Gackt out of Malice Mizer & the other members couldn't stand him being so controlling so Malice Mizer disbanded.
*sigh* No. Again. Mana is a perfectionist, this is clear enough. He wants things done exactly right, & if that means doing them alone, then so be it. I believe that's why he started his solo project Moi dix Mois. He's stated he doesn't feel the need for conversation with others who don't understand his creative vision. This doesn't mean he's a bitch, just he's very individualistic.

Rumour #4- Mana is really a woman.
o.O No. If you want proof look at his jawline. Or at his crotch when he's getting out the car in the Invite to Immorality live Europe tour DVD.