Is it morally wrong to start a friends with benefits arrangement while dating someone else?

I’ve been dating a woman for almost two years, but she hasn’t wanted to make things official despite spending almost everyday together, we’ve met each other’s friends and families, and gone on three overseas trips together.

There is this girl in my social circle who is interested in me and I’m thinking about asking her to be friends with benefits?

Would it be wrong to pursue this?
Is it morally wrong to start a friends with benefits arrangement while dating someone else?
Post Opinion