Shizuka is Godou's sister. Shizuka appears to care for her brother, but is often extremely exasperated by his actions, especially the fact that he's such a lady-killer, and doesn't even know it. Sometimes acts as if 'she' is the elder sibling and Godou is the foolish younger brother. She's the one person Godou is truly scared of.
Godou and Erica have a very complicated relationship. Neither of them liked each other at first but later on Erica fell in love with Godou. Erica has even declared herself to be his lover, wife, and one true love, and Godou argues against this at every chance. However, he has privately admitted to himself that he does find Erica very attractive, and that there seems to be an connection between them, but finds her drive off-putting, as he knows if he gives even an inch, he will be wrapped up and all but married to her in no time. He 'does' get frustrated by her claims which many take at face value, believing the two to have already been intimate. Despite running away from her, he has said it to himself that she is one of his most precious persons. In the end, Godou found himself falling for Erica even to a point where he couldn't live without her. They do have a confusing relationship but Godou and Erica have a deep connection.
At first, Yuri thought Godou was a fearsome tyrant because of her previous interactions with a Campione, but still attempted to convince him to be more modest in his actions with Erica. However, as time passed and the two interacted, she discovered most of the actions were on the part of Erica, and began to fall in love with Godou, though she is not yet willing to admit it, possibly even to herself. In Volume 5 Yuri has admitted that she has feelings for him and in Volume 7 she swore allegiance for life to Kusanagi Godou until one of them dies.
Liliana is Godou's trusted knight. She tries to convince Godou and herself that most of the things she does for him are because she is his first knight and therefore responsibility falls to her given the circumstances. Both of them are shown to have feelings for each other. In Volume 18 Chapter 10, it is revealed that they are both aware of their feelings for each other, but under pretext of lord and knight, although they are dating like a lover.
Originally, she simply watched Godou's relationship with her sister from afar. After being rescued by him, however, she seems to have developed feelings for him.
Godou thinks of Ena as a friend, though Ena said that she wants to be Godou's lover, and if possible, his wife. She always says that she is Godou's woman which causes misunderstandings (mostly for Annie Charlton) though Godou finds Ena to be very cute and very beautiful.
Godou finds Salvatore to be an idiot, often calling him 'Idiot Doni' and he always refused that Salvatore is his friend. Though Salvatore finds Godou to be interesting, he's willing to lend the 'Book in Praise of David's Great Works' to Erica just so that they can protect Godou better. Salvatore declared Godou as his 'Eternal Rival' but still Godou thinks of him as one of the stupidest people in the world!
Originally enemies, or perhaps opponents, Luo Hao has adopted Godou as a younger brother, and has vowed to teach him how to be a Campione. There are some indications that she's romantically interested in him as well.
Godou likes her well enough, but thinks that she's as crazy, and as dangerous, as Salvatore is stupid in her own way.
Godou dislikes Voban, but acknowledges he's a dangerous person, like a wild wolf. Voban hates Godou as well, for thwarting his will.
She helps Godou in different ways to fight Sun Wukong and as she keeps seeing Godou fight she feels respect for him. Annie which is John Pluto Smith's daily life develops a romantic interest in Godou seeing him as a hero of sorts.
Heretic GodsEditAuthorities and his personality changed, Godou felt responsible for the change in the youth he befriended and decided that he can't leave him alone. This is something that leads in him to battle Verethragna with the help of Melqart and the power of Prometheus' Grimoire and eventually resulted in Godou becoming a Campione.
At first, Athena thought of Godou as an enemy, and gave him a 'keep out of my way' attitude. After finding out her plan to envelop the world in darkness, the two became true enemies, but Godou was willing to be merciful to her.
After Godou defeats Athena, Athena seems to have adopted a 'wait and see' attitude as to how to act with Godou, and has at times provided aide to him. She seems to still be deciding whether or not he is an enemy of hers, or possibly something like an ally, a friend, or even more. Thus Athena develops feelings for Godou.
When she finally had her final battle against him, Athena won, but didn't slay Godou. Instead, she chose to grant him a gift from her divine wisdom. This is the first known case of a Heretic God granting a Campione power of their own free will.
Ever since the battle with Athena, Lancelot has been looking forward to fighting Godou in a passionate life and death duel. She doesn't have any problems with teaming up with him (even though she used her Authority on him). She has now become his Authority (Lance of White Knight).