Bio: The life and times of one happy gay boy living peacefully with his long-time partner and eight cats in Richland (south) Georgia.
Is it proper to say in the text: "With his long-time partner or is it with MY long-time partner?
If this is a subtitle, you'd use "his" in any case, since you haven't introduced yourself yet. You've only made reference to "one happy gay boy". Your next task is to start writing in the first person so that your readers know it's an autobiography, and that the title refers to you.