Causes he know that she is a part of sora that why
No, Riku does not love Xion. Xion is Sora's lost memories, so he wants to help Xion to help Sora.
No, Riku and Xion only share some conversation in the new Kingdom Hearts 358/2 Days game.
She is in various places with Riku
Kingdom Hearts 358/2 Days spoilers:Xion first met Riku at Beast's Castle, during a mission she had with Roxas. They had a fight there over who's right; Riku, which claiming Xion and her key-blade are fake, or Xion, who is getting mad at him for calling her this way and says he's the one acting fake. He knocks her and leaves the place, while Xion is on the ground, defeated, and screams in pain.Later, Riku had seen cradling a painful Xion in his arms, back at Destiny Island. Xion had a nightmare about the scene in Kingdom Hearts Chain Of Memories, where Zexion gives Riku an hurtful speech about how he destroyed his home and forgot his friends. When Xion awakes in Riku's lap she asks him who is he. He answers his name is Riku and that he's Sora's friend. He tells her who she really is, and she asks if he hates her for rubbing his friends away from him. He answers that he does not hate her, but he is sad. She apologized, saying that she still don't want to disappear so he gave her time to think.In one scene Xion's hugging her knees, looks like she's crying in her bed, back at The World That Never Was, and asks: "What should I do... Riku."The two also later shared a conversation in Twilight Town.
Axel wants Xion to return to Organization XIII, but she wanted to return to Sora. At the same time, Xion pretty much wantedto be eliminated, because Namine told Xion that if Xion returns to Sora, she'd return Sora's memories so he can reawaken and destroy Organization XIII.
Defeat Riku (after Xion)
Axel was ordered to stop Xion from betraying the Organization. Xion was important to Organization XIII and their plan on harnessing the power of the Keyblade, so when Xion was informed by Riku of Org. XIII's plans, Axel had to stop her from further interfering.
i have no idea, but personally, i think he might have like xion ,in 358/2 days for DS
OF COURSE RIKU NEEDS A GIRLFRIEND! Luckily since I'm making a book based on Kingdom Hearts( Sorry Tetsuya Normura,I was going to give a good idea for you) my main character (NOT SORA) Mitsuki Hikaru will be Riku's girlfriend.
The King, Sora, Goofy, Riku, Xion, and Donald
The Keyblade Wielders are Sora/Roxas/Xion,Kairi,Riku, ,Ventus/Vantais,Terra,Aqua,and Master Equas
i think Axel, Roxas and Riku are definitely the hottest guys. Xion and Namine are the hottest girls.