He could also be in denial at first. It's such a big change and he has a lot of baggage. He might think it's some sort of trick or a situation that will bring more trouble than good. But as time passes, he slowly comes to accept it and embrace his new role.
Klaus may be overjoyed. Given his complex character, he might see this as a new beginning, a chance to create a family of his own in a way he never thought possible. He could immediately start making plans to ensure Caroline and the baby are well - cared - for.
Klaus might be overjoyed. He has always been attracted to Caroline, and having a baby with her could be the ultimate sign of their connection. He would probably be very protective, using all his power and resources to keep her and the unborn baby safe.
Klaus would be very attentive to Caroline's pregnancy cravings. He'd see it as his duty to take care of her during this time. He might cook for her himself if he can, or take her to the best restaurants to get what she wants. He would be a bit overprotective too, making sure that whatever she eats is of the highest quality and safe for her and the baby. He'd also listen intently to her when she talks about her cravings, finding it endearing and a sign of the new life growing inside her.
Klaus might be overjoyed. Given his feelings for Caroline, the news of a baby could be the best thing he's ever heard. He'd probably immediately start thinking about how to take care of Caroline and the child, using all his resources.
At first, he might be shocked and a bit scared. But then, Klaus would probably become extremely possessive and overprotective. He'd use his power to surround Caroline with security. He might also be a bit more tender towards her than usual, as he realizes the importance of the new life they are about to bring into the world.
It could become more intense. They now have a shared responsibility, so they might be more connected. Klaus might be more tender towards Caroline, and Caroline might start to see Klaus in a different light, perhaps more as a partner rather than just an acquaintance.
Her friends might be shocked at first. Bonnie, for example, would probably be worried about the implications of having a baby with Klaus, considering his past. But she would also be there for Caroline, offering her magical support if needed, like protection spells for the baby.
Bonnie would probably be very protective. She would use her magic to ensure Caroline's safety during the pregnancy. She might also be the one to encourage Caroline to be strong and not let Klaus's absence break her. Elena, on the other hand, would be more empathetic, sharing her own experiences of heartbreak and trying to help Caroline through the emotional turmoil.
Klaus might be initially shocked. He has so much on his plate already with his power struggles and family issues. But then, his protective side would likely kick in. He's a very possessive character, and the idea of having a child with the reader would make him determined to keep her safe at all costs.
In some fanfictions, Klaus's first reaction could be one of suspicion. He has been betrayed many times in his long life. So when Caroline shows her feelings, he might think it's a trap or some sort of ploy. He would start to question her motives, but as he looks into her eyes and sees the honesty there, his suspicion slowly turns into a warm feeling of acceptance and love.
Their relationship likely becomes more intense. With a baby on the way, they have a deeper connection. Klaus might become more tender towards Caroline, showing a side of him that few have seen. Caroline, on the other hand, may start to rely on Klaus more for protection and emotional support.