Gaining

Was she this size when you met her? If she was, then tell her that you've always been attracted to her just as she is and wouldn't want her to change.


Then take her out for dinner lol

Tell her jokingly you want her to gain weight. If she freaks out, you can always tell her that you were kidding, but then tell her you want her to stay the same. Even if she doesn't try to gain weight, knowing that you like large women may cause her to relax and put on some weight.