Bailey's Irish Cream Fudge

This is an "adults only" fudge.

4 1/2 cups granulated sugar
1 (12 ounce) can evaporated milk
1/2 pound butter
2 (12 ounce) packages milk chocolate chips
1 (12 ounce) package semisweet chocolate chips
2 (7 ounce) jars Marshmallow Cr