Physical attraction is a must if the relationship is going to be an intimate one eventually. Is it everything? Obviously not. Many prostitutes/gigolos are physically very attractive (they earn their living with their looks!). But who wants a gigolo as a boyfriend/husband, or a prostitute as a girlfriend/wife?
Birds of a feather are attracted to, and stay with each other in the long run; for good and obvious reasons (think about them). If you find a couple who on the surface looks like they are polar opposites, don't be fooled by your eyes, lift the table cloth and look what is under the table.
Focus on the kind of guy you want (meaning you have to figure that out first) until he shows up. In your case, it looks like neither A nor Z is a good boyfriend choice for you. Accept no compromises which only means you are compromising your happiness.
For Z, if he is not your physical type, you can do the following NOW to prevent hurting him one day.
How to Tell Someone You Just Want to Be Friends?
Try subtle hints that let the other party know that you're not interested in romance. For instance, "I really value our friendship" (with emphasis on "friend"), or "It's so nice to have a guy/girl friend who I can talk to without any kind of romantic tension to get in the way."
Mention that you're involved with someone else (assuming that's true) if the other party is a new acquaintance and shows unwanted romantic interest.
Tell the person up front that you enjoy being single right now and are not looking for a romantic partner, but that you're always looking for new friends.
Make a joke out of your rejection if the person is an older friend: "We'd never make a good couple; we know each other's hang-ups too well - there'd be nothing to argue about!"
Be honest and tell your friend why you don't think a relationship would work out, unless the real reason is that you aren't attracted to him or her. Even the closest of buddies would have a hard time rekindling a friendship after such a harsh rejection.
Change the subject after you've dashed the notion of romance and try to forget about what just happened. Dwelling on the reasons why you don't want to get involved with a friend won't do the friendship any good.
Enjoy the friendship as you always have.
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