Spencer Pratt claims Heidi Montag has made him less evil.

The reality TV star believes he and his spouse - who he wed in November 2008 - have grown more similar the longer they have been together, and he credits his wife's ''sweet'' outlook on life for making him change for the better.

He said: ''We have become more similar, I have tried to be more like Heidi. She has stayed sweet and loveable and fun. I used to be way more evil than I am now. I was in all these secret societies - places where powerful men hang out, there were rituals, things you wear... It started at university. I'm not a part of it anymore. Just places where powerful, wealthy people help each other along. They've been around a very long time. Not evil, a little dark maybe.

''Heidi has no dark side. She brings out any light I have.''

Heidi believes the couple still have some personality differences, but their core of shared values is what makes their marriage work.

She told OK! magazine: ''Spencer and I are very similar but we are very different. We are compatible. At the core, we have the same values, morals and principles. Little details are different, but that's what makes it fun.''