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QuestShipping is the belief in a romantic relationship between Jimmy (Kenta) and Marina. The evidence for this can be found in two places in The Legend of Thunder!. The first is in Part One, in the scene with them talking outside the Pokémon Centre. There are a number of subtle hints, particularly from Marina. Interestingly enough, many characters do notice this, including Vincent and Typhlosion.
Opposers to this ship point out that Jimmy made it clear that he had no romantic feelings towards Marina. However, supporters say there are still hints in the conversation and that "he just doesn't know it yet". (And bear in mind that that has been said about Ash a lot.) Indeed, similar to Pokéshipping, it is Marina who shows the most hints of romance.
Near the beginning, when Jimmy is speaking to Vincent over the phone, Vincent beckons him closer and says, "You love her, right? Ever since we were kids..." conversation Jimmy blushes, denies it, and slams down the phone. The key piece of evidence is found on Part Three when Marina lands on Vincent. The next scene between Jimmy and Marina makes it pretty conclusive that there are romantic feelings. Vincent stops it, but not before allowing enough proof to make this a very likely ship. Then, in the end, right after Vincent, Jimmy, and Marina take separate roads again, they show a scene where Jimmy is walking through the forest. His PokéGear is ringing. It's Marina, who's asking him if he wants her number. Jimmy calmly says "Yes", but is blushing and making a "Yes!" gesture as he receives her number. Yes GestureTemplate:Shippingstub