
I believe he got worked up because he thought that Shuri might be cheating on him/ envisioning to leave him after for another man etc. or perhaps he was just afraid of rumours circulating and stuff? but i think it’s the first option since i seem to remember he was interrogating her about what “that man” promised to offer her

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If I remember correctly, the necklace came from the emperor as a gift. Johannes, was originally in love with the emperors first wife who looks like shuri (there’s a lot of information that will be revealed about how this relationship affected the whole story later). Her looking like shuri is one of the reasons he married shuri, and because the emperor ‘stole’ his first love, johnannes, in a state of paranoia, thinks that shuri is cheating on him with the emperor.
Lost of highly complex characters that make the story’s character relationships rather interesting.

I didn't read the novel but I feel like the necklace being from the emperor makes a lot of sense cuz i think he also sees ludovica in shuri but he also believes that johannes marrying a child is unethical, hence the necklace being given, i guess as a way to show his support (maybe he believes that shuri was forced into the marriage). But still it was also unethical for him to send fricking necklace to a child like bro have some sense people would obviously think the worst.
I am at ch 100th and confused as fukk about who sent the first necklace? Why was Johannes so worked up??