Adding an image map to the background

Hello,

I’m currently in the process of redesigning my website but was just wondering if anyone knows how to make a sort of image map for the background image?

What I want to do is to have a more attractive link to the forums by clicking a character that has a speech bubble (here’s an image of a rough draft of what I want https://nintybuzz.com/Screen%20Shot%202016-05-09%20at%2013.28.36.png ), I was also thinking it could be useful to know in the long run to try and do some fun things to increase user interaction ??

Thanks in advance
Leon