Fat experiences

So after my partner had unintentionally gained some weight during the past year (super hot!) she has now stopped gaining and has even lost some weight (around 5-6 lbs during the last month or so, which I wouldn’t have known if she hadn’t told me about it) according to her the weight loss was also unintentionally, even though I know the gain bothered her...
The thing is, she is still getting wider and softer all over, and she had even out grown some pants during this month...
Now this is supper hot to see her get wider and softer, but I must ask, does this make sense?!
How is it possible, how does she continue to grow while losing weight? If I didn’t see the numbers for myself I would have been sure she was still gaining (based on her looks and current weight 5-6 lbs are negligible)

Is this normal?
Did anyone experienced such a thing?

My guess from what I've read on this site would be that maybe she's 'losing' muscle (which weighs more) or she's losing visceral fat which from what I've heard is easier to lose than subcutaneous fat?

If she's getting wider and softer, it's probably subcutaneous fat gains. But as for the weight loss, it could be a lot of things. Personally, I think it's water weight.

Thanks!
Muscle loss does sound like the most reasonable thing... she has been less active during the past few months with her new desk job

Definitely muscle loss!
Just the other day she had a sore muscle from changing her sitting position...