When I first discovered Conan I thought it was fairly obvious that Shinichi/Conan loved Ran and she loved him. End of story. However, when I encountered Conan fandom I found out that there were quite a few people that believe that Conan loves Ai Haibara. Now, my first response was to go: 'Huh?? Where did they get _that_ idea!'. But I have since discovered some of the reasons why there are Conan x Ai/Shinichi x Shiho fans out there and I have to admit that there does seem to be some evidence pointing to a possible feeling between them... yet this in my eyes this is not conclusive enough for me to subscribe the view that Conan _loves_ Ai.

Now, before I continue I would like to reiterate that all this is _my_ opinion and I am not trying to bash anyone who likes Conan x Ai. If I come across that way, I'm sorry! ^_^

From what I have read and seen in both the anime and manga, I do think that Ai does have some feelings for Conan. He often surprises her and she seems to admire that. Her expression in volume 18 when he refuses to admit that the murder is impossible to solve indicates that she had some sort of preconceived ideas about him which he is rapidly demolishing. There are frequently times when she lets out hints that she likes him a lot In volume 20 she says (in response to his earlier question about her true age): "I'm 18, just perfect for you." When Conan stares at her in confusion, she smiles and says: "Just kidding." This follow-up is one she seems to use a lot , so it's not entirely obvious that Ai means what she says. However, her expressions often say more than her words and there are several instances which indicate she has feelings for him. Another possible indication is her seeming dislike (or jealousy?) of Ran. For a long time, Ai avoids talking to Ran and often thinks to herself: "Am I running away from it?" The question is, what is 'it'? If Ai is jealous of Ran and the place Ran has in Conan's heart then it would seem that she is in love with Conan...

So, if we say Ai is in love with Conan, or at least likes him a lot, then can we say that Conan knows and returns her affection. Well, personally, I don't think he loves her. To Conan, Ai is an ally and now a friend. She puzzles him, that's true, and I don't think he's entirely sure what to make of her little comments, but then... Shinichi was never exactly good with romance, and Conan is still Shinichi. Sure, Conan talks to Ai a lot and in more depth than many others, but that's because she is one of the few people he _can_ talk to as his real self. He can't share with Ran, she's nearly discovered him several times and he doesn't want to risk her finding out. Notice that Conan talks extensively Heiji in the same manner as he talks to Ai.

Yes, I know there have been a few points where Conan seems to go an extra mile to help Ai and a lot of Conan x Ai fans have pointed out the Bus Jack case in volume 29. Sorry, but I don't call that conclusive at all. Conan would've smashed through the glass of the bus for _any_ of his friends. This is the guy who (as Shinichi) helps Ran save a serial murderer from falling (volume 35). So, he is concerned for Ai? He was very worried about Heiji in volume 23 when Heiji disappeared aboard a ship. You might as well say that Conan is in love with Heiji as say that he is in love with Ai And before anyone points out the mass of Heiji x Shinichi doujinshi around in Japan, I am _not_ going to get into a debate about that as I definitely don't see it as a possibility - especially on Shinichi's part.

However, there are definitely many, many indications of Conan's feelings for Ran. In the very beginning of the manga Shinichi is shown to be thinking about Ran in a romantic way. Perhaps he was even working up to a point where he was going to tell her his feelings? He gets furiously jealous when he sees someone hitting on Ran (or thinks someone is), just see volumes 5, 11 and 24 for some good examples. When she is very close he gets flustered and finds it hard to think clearly... and this had been a problem before Shinichi was shrunk as seen in volume 21. There are many other small things and some big ones (volume 26 - Shinichi taking Ran to the same restaurant, the same table where his parents got engaged) that show he loves her and I don't think Ai is going to oust Ran from his affections that easily.

So, in conclusion, I don't think that Shinichi/Conan loves Ai. He mainly regards her as a friend and ally who needs some looking after and his true affection continues to lie with Ran. However, it is entirely possible that should anything happen to Ran (hopefully not!) that Conan might fall in love with Ai, but it would be a feeling that takes a while to grow as I'd imagine that Conan would be devastated if Ran was killed or fell in love with someone else (unlikely, but possible).

Postscript: One of my biggest problems with Conan x Ai fanfic is the ease that Conan falls in love with Ai and all his affection for Ran is discarded quickly. Or Ran is villified to the point where she is not Ran at all, but some violent idiot getting in the way of Conan and Ai's romance. I'll read a Conan x Ai fanfic, but only if the relationship is well thought out and developed logically! ^_^