I have a question that I think should be left for the more experienced gm's on this site. I ask this because I do not want to be labeled a thief for even thinking about doing this but it pains me to see it the way it is now.

The question is if it's okay to steal an rp idea without the original gm's permission but let me explain that this was a soul eater rp and didn't make it past two pages. I think that if it was rebooted their would be people ready to take up the spaces. I did ask permission buy the gm herself hasn't been on the site for 5 months. So again is it okay to take the idea and reboot it myself?

If the player has gone inactive, particularly without sign of coming back, go for it. Just give credit to the contributor(s) of the original idea where it's easily visible.

As long as you alter it so it is at least different. I'd sure as hell be pretty annoyed if someone came along and jacked my gundam rp and I was really aggravated to see three power rangers rp's just flop up as soon as I made one. The same can be said of the rosario x vampire rps that happened due to my own rules interfering with things.

Yeah, just credit them for the idea, and close it down if they come back and ask you to.