Based on red slime girl getting plowed by 2 cocks i'm thinking a Multiple penetration tag is needed...maybe a swinging or netorare tag as well. I love MP so it's the kind of NTR i can support, but it IS (maybe) another cock in your girl. Unless it's not your girl despite harem tag suggesting all girls are MC's girls. Whatever, do with that one what you will...but MP seems absolutely necessary.