I understand why the question irritates you, especially if it's asked repetitively. But let me turn the question around and pose it this way: What do you a call a man who dates women, fucks women, loves women, has absolutely no romantic feelings for men, has no desire to touch men sexually, doesn't find cocks or the male body remotely attractive ... but will, on occasion (especially if horny enough and drunk) allow a man to suck his cock?
Because these men exist. I've had their cocks in my mouth.
Apparently some of you would simply say, "those guys are bi."
But doesn't it seem ridiculous to describe men like that with the same word we use for men who openly proclaim their ability to not just fuck but love both men and women?