light - he's happy he no longer has to lie to you and is excited to rule the new world by your side.
l - he expected you the whole time but didn't want to believe that he was right since he is in love with you and hasn't felt this way about anyone before. if you told him he would probably go into shock but have to arrest you :(
misa - she's so happy!! loves you even more and helps you with her shinigami eyes!!
matsuda- he's scared at first but he was always sympathetic towards kira so he eventually ends up agreeing with you and using his position as a police officer to help you! he's impressed by your strong sense of justice.
ryuk - he is surprised that there's another death note in the human world and is excited to see what you do as kira.
soichiro and aizawa - they would arrest you if you told them :(