Re: canonmate permapairs - We do heavily encourage crosscanon pairings, but ultimately, permanent match-ups are up to player discretion, and canonmates pairing up is not disallowed!

Re: permanent pairings sleeping with each other - doing so is ICly disallowed by the Admiral in all cases, and it would result in an immediate depairing. What would invite demotion would be doing so particularly flagrantly or unapologetically, or using force/manipulation. However, if you are interested in a ship between these characters that gets physical, they won't be able to stay paired, even if nothing fully demotion-worthy is done. Pining/lust that they abstain from acting on would be fine.