I have never really been big on condom use either, I discovered back in high school, when my husband and I were still fuck buddies, that I have an allergic reaction to most spermicidal lubricants. This isn't to say that we didn't use them, but it was never pleasant afterwards, but I was dating 2 other guys and sleeping with at least one of them so we wanted to be careful but once I realized that I was falling for him and sent the other guys packing, bare back became the norm, especially once I was on birth control. I've had an IUD for the last 6 years, so the couple of experiences I had with other guys, in the context of foursomes, did not involve condoms, but they also didn't involve fluid bonding, as the males would always cum in or on their primaries.
With my boyfriend there was no work up to fluid bonding, we'd set the boundary at oral only and so our first intercourse caught us completely off guard and left us reeling, at how powerful the connection was, the fluid bond and how right it felt, but also at the realization that we'd crossed the boundary, broken the rules, and now had to tell our spouses/ primaries what had happened. Thankfully it all worked out in the end, because I can't imagine not having that connection with him.
Within our quad there is no condom use, though the unspoken rule is that if there is a potential to have sex with anyone outside the group you must use protection.