I'm just reading again what I've read before:
You can sponsor a conjugal partner if:
- there is a significant degree of attachment between the two of you, implying not just a physical relationship but a mutually interdependent relationship, and
- you’ve been in a genuine (real) relationship for at least 12 months where marriage or cohabitation (living together) hasn’t been possible because of barriers such as sexual orientation, religious faith, etc.
So in IRCC terms, if there is no significant barrier preventing you from marriage, you can't apply under conjugal partners category.