Need help, is this cum stain?

Gf told me that she is going to cinema with her female friend, when I came home she was already asleep and I found these panties in dirty laundry, they were still wet and warm, with a bit different smell than usual. Never ever her panties looked or smelled like this. Do you think it could be creampie stain? I pitched this idea few times but she isn’t into this. Thank you for your advice
Yes that's a creampie
 
  • Like
Reactions: Cuckindeep