I would like to see another line added, that if he is only seeing the Tav and that is commits himself to a monoship.

Just in addition to what you said, it feels like a monoship, both date exclusively each other so why not make it official? Make him willing to explore this path with Tav and that's it.

3 options:

1) Tav: I want to live and love as open as you do, Halsin (but then he should actively date others)
2) Tav: I love only you and want us to be exclusively to each other
3) Tav: I wish to only love you but you are free to roam, Halsin (this is should also include him actively date others)

and then Halsin's reactions:

1) Perfect. (couldn't come up with something better lol)
2) I never explored this wonderful tamed garden of your's but my heart is more than willing to do so.
3) If that is what your heart desires, you may have it.

All of those option include Halsin calling it a relationship (it's not a casual fling or just friends with benefits). He says a lot of sweet things but afaik he never told you he loves you (correct me if I'm wrong).

This allows each player to get what they desire and it shouldn't take too much effort. It's all about Halsin's commitment, stuff needs to be canon and not headcanon based on ambiguous lines.

If you want to answer to any of my posts with just hate, please just don't answer at all.

If you want just to white knight everything and can't accept opinions, please don't even answer me.

Thank you!