This is my gfs most used dildo vs my cock. Size definitely matters to her.

This is my gfs dildo vs my penis.
Since I found it I always imagine her with a huge dick.
I know that she is kind of open to the idea of not being monogamous since she let her best friend suck my dick once. But she never showed interest in any other guy and when I asked her she told me that she doesn't want or need anyone else.
I don't really know how make her fulfill my fantasies without pushing her too much.