I like jealous Barnabas headcannon. He deserves to be obsessively jealous about his dear Jonah. I think he actually didn’t have any other close relantionship but Jonah because he was afraid they will steal him away. Also I like the idea Barnabas’ willing to do complicated schemes to prevent Jonah from spending time with anyone but him.
“Ooops I’m so sorry my dear the handle fell of I guess we will be trapped in this room for a while and you’ll sadly miss that important meeting with Robert.”
“Oh no, I spilled wine on your shirt. You cannot go out like that! What if instead of visiting doctor Fanshawe you went shopping with me I’ll buy you a new one.”
“I’ve heard Klempthorne feels a little bit sick. You wouldn’t want to risk falling ill right Jonah? Let me just send him message you won’t make it.”