Well, this answer might get a bit complicated.
It's difficult to say "why" Solomon loves Saya, given that most people tend not to quantify love in that fashion, and thus don't really have a particular reason why they love another person. However, one could say that, in addition to whatever feelings he's developed for her over time, Solomon feels somewhat the same way as Karl does in regards to Saya.
Karl loves Saya because she has Diva's destructive power and appearance, but actually interacts with him a way that Diva does not (in his own, warped case, attempting to kill him functions as an interaction and bond).
Solomon, meanwhile, has a somewhat healthier mind and outlook: she is very much like Diva, whom he loves dearly, but more personal, grounded, and mature. Whereas he can hardly count on Diva to so much as look at him on any given day, Saya is a more stable individual more willing and capable of loving another person (though, as the audience comes to realize, Solomon might not be that person). Any other feelings he has for her could potentially be built afterwards, with this interaction as a base.
Or I could be totally wrong. Who knows?
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Because she's a self insert character for the female viewer.
He is Saya's chevalier, he is always with her and when he is not he is waiting. Saya belives he and her have more of a family like relationship,but Hagi is in love with Saya.
In 'like' as 'love', probably not. But it's possible. In 'like' as in just 'like', well, maybe. He's insane, remember? It's not clear whether or not he likes Saya because he's like that.
They can't have children because they both have the same blood.
You mean Riku? Well, he gets killed by Diva Saya resurrects him by turning him into her chevalier Then Diva rapes him and she accidently kills him, killing him permanently
No he does not. At the end of the last episode Haji leaves a rose with a ribbon tied around it for Saya at the grave.
Solomon interests Saya but Saya loves Haji and Haji loves Saya.
Saya Kai Hagji Diva Solomon Mr.David Riku
Yes, he is swiped by the sword that has Saya's blood on it during the fight with James in episode 46.
He is Saya's chevalier, he is always with her and when he is not he is waiting. Saya belives he and her have more of a family like relationship,but Hagi is in love with Saya.
Hagi loves only one person and that person is Saya
5'2"
In the anime Blood Plus+ Haji is the "chavelier" or protecter of the main character Saya. He restores her enerygy by letting feed off of his blood. He is immortal and lives only to serve saya.
In 'like' as 'love', probably not. But it's possible. In 'like' as in just 'like', well, maybe. He's insane, remember? It's not clear whether or not he likes Saya because he's like that.
I'd say about 48+
Honestly, yes he is. He is the male protagonist right after the main protagonist Saya.
They can't have children because they both have the same blood.
You mean Riku? Well, he gets killed by Diva Saya resurrects him by turning him into her chevalier Then Diva rapes him and she accidently kills him, killing him permanently