Larian Studios Forums Baldur's Gate III Baldur's Gate III - Story & Character Discussion [SPOILER WARNING!} Retaining the Slayer Form: A Proposal for Player Choice in Dark Urge Quests

Remember that you were slain by Bhaal and Withers brought you back. And I don't think the Bhaal Slayer form could be brought back with you.
You're still Bhaal spawn though, and even without the slayer form, you will be reminded of it throughout the game.
I don't know if you finished the game already, but the most poignant reminder , I think, was during the feast after the adventure is over, and we celebrate the victory and friendship. If Jaheira is there, she may tell you that her children have come to Baldur's gate city to help with the repairs. She then asks if you will now now found a family also. One of the answers is "no, the bhaal spawn ends here".
That's one of these moments in the game where you just sit, glued on your chair, while the meaning of what you read sinks in slowly.
It could be another hug moment, but one for you the player.