Youd be surprised. Office ‘wives’ and ‘husbands’ are a very real thing - and in most cases it’s not a sexual relationship. I see it all too often. To be perfectly frank, it is usually between extremely ambitious women that attach thenselves to men they see as being both able to help them advance their career as well as extremely susceptible to manipulation. I have had to have ‘talks’ with more than a few of these couples - and had to move one or both on a few occasions. They are extremely destructive influences in office environments. Good management is on the lookout for such situations and head them off as soon as it appears to become apparent.
That said, i am reasonably sure these 2 actually took it to the next level. There wouldnt have been the need to not produce certain texts and ‘attachments’ if it were purely platonic.