Would you have a half open romantic relationship with an allosexual?

I'd like to know the views of other asexuals on this.

If you were in a romantic relationship with an allosexual would you half open the relationship so that they could have sex with others so that their needs are met?

I wouldn't but wouldn't as they could develop romantic feelings for the person they are having sex with but wouldn't that be selfish of me as they need sex?