When a guy asks this question, there could be a lot of reasons for asking:
1. He might want to compete against other guys (“Am I better than other guys?”)
This is him seeking a straight up ego-booster. Here, he is wanting to feel more manly. If your man is seeking this, you might need to pad the truth a little for him to receive this.
2. He might need validation on his manliness (“Is my size attractive enough for you?”)
This is him seeking comfort for his insecurity. He wants to know if he is desirable. He wants to feel sexy. Here the truth may hurt a little but if you speak the truth with love and address the deeper issue, he’ll feel a lot better. Sizing is not the only thing that can make him sexy. [If you] give him bad news, tell him how he may be able to be sexy for you. This could be how he plays with your body in foreplay, or the way he looks into your eyes, etc.
3. He might want your judgement on its efficacy (“Can my tool satisfy you?”)
This is him wanting to know how to please you. Size is an easy way to verbally summarize his performance to get you there. But we all know that there are so many variables to getting you to climax. It could be the speed, the skin-to-skin contact, the sounds, your mood, how much you trust him, his attention to certain body parts, etc. Here I would still be honest. But again, don’t leave it at a “it’s too small/skinny/etc.” Tell him why it’s important. It could be that you would like the depth of penetration or the stretch that it makes. This gives him more things to go on and helps him understand what you actually like.
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