Someone who is monogamous or who has a monogamous relationship has a sexual relationship with only one partner. Do you believe that men are not naturally monogamous?
(used of relationships and of individuals) having one mate; "monogamous marriage"; "monogamous for life"
monogamous.
Heceleme
mo·nog·a·mous
Etimoloji
[ -mE ] (noun.) 1612. French monogamie, from Late Latin monogamia, from Greek, from monogamos monogamous, from mon- + gamos marriage, from gamein to marry.