We actually don't know much about the mother of Peter's wife in this story. All we know is that she was sick and Jesus healed her. There are no details about her name, her background, or what she was like as a person. The focus of the story seems to be more on Jesus' act of healing rather than on her as an individual.
No, it is not appropriate at all. Such topics are very private and often fall into the realm of vulgar and inappropriate content that should not be shared publicly.
Definitely not. Common phrases are those that are widely used and easily understood by most English speakers. This phrase is so unclear and jumbled - looking that it can't be considered common. It seems more like a very specific or even made - up phrase by someone for a particular, perhaps very private or idiosyncratic, reason.
No. Such stories involve private and inappropriate content. In a healthy relationship, respect and privacy are crucial. Sharing such intimate and improper details is disrespectful to the partner and violates the boundaries of a proper relationship.
Well, if this is a story someone has shared privately or within a certain community, it might involve the experiences of a big - beautiful - woman (bbw) wife in relation to a first - time anal experience. But again, without details it's just speculation.