Gaining

Congradulations on having some results with your girlfriend and some weight gain. It is very exciting and fun to see even the little things such as you mentioned her complaining about her works pants being uncomfortable...watching her appetite increase and her being able to eat more etc.

How old is your girlfriend? You mentioned she has a fast metabolism but is she interested in trying to gain with your liking it and does she talk about it with you?

One question to ask yourself is: do those few pounds make a difference in how attracted to you are on their own, or are they mostly important to you as signs that she is gaining, and they could be the first step towards more?

I think it would be great to tell her how fantastic you think she looks, and find any places where the weight has made a difference and pay them extra attention. But totally not cool to do it in like "Great, you are finally gaining weight, that is a nice start and I can't wait until you gain more."

Also one tip: if she's having to do up her shorts with a safety pin, she isn't close to needing new clothes, she needs them now. She might be able to wear her current clothes, but they probably aren't comfortable and they sure won't be maximally flattering (sexy to you maybe because they highlight her gain, but not generally flattering). She might feel better once she has pants that fit properly. AND she gets rewarded for what she's gained so far, which helps show that you appreciate even this little gain.

And if she never gained more than this, how would you feel?