It's definitely a majano. People consider them a pest anemone, but IMO they aren't as bad as Aiptasia. Aiptasia spreads like wildfire, but majano isn't nearly as bad, and some are quite beautiful. I've seen some that are better looking than any "desireable" anemone on the market. I would remove it because it will eventually start to take over your refugium area, and they don't really help your tank any. If something were to happen and a bunch died at the same time the resulting ammonia spike could do some serious damage to your tank. Maybe you could start a small species tank for different attractive majanos? Many LFS would love to give them away.