Shion was originally hostile towards Rimuru under a misunderstanding that involved the destruction of her home village. After the misunderstanding was cleared and Rimuru names her, Shion became extremely loyal to Rimuru and holds a deep affection towards him to the point she loves him.
They both are the most devoted subordinates of Rimuru, while also both competing for the position of number one Secretary of Rimuru, making them rivals of sorts who actually do seem to get along very well otherwise.
Apparently Ranga and Shion are sometimes very close partners as seen during the fight with Charybdis. Ranga learned the art of holding back from Shion.
Before meeting Rimuru, Benimaru was Shion's superior. Shion and Benimaru seem to get along with him and are good friends with each other. Comically, she appears oblivious to how much Benimaru fears her cooking. While Shion is loyal to Benimaru, she's not above hurting or punishing him when it comes to certain matters like Rimuru or her cooking.
Shion holds high respect towards Hakurou and are good friends with each other. Comically, she appears oblivious to how much Hakurou fears her cooking. He taught Shion the basics of swords arts. Hakurou views Shion as his own daughter.
Shion and Souei seem to get along with him and are good friends with each other. Comically, she appears oblivious to how much Souei fears her cooking. Her childhood friend from the ogre village.
The elite guard under Shion with Demon Lord Dagruel's three sons as its officers. They are the Hobgoblins and Goblinas who were killed in the Falmuth attack and then revived, giving them the extra skills Self-Regeneration, Perfect Memory, and Pain Nullification, effectively making them into nigh-unkillable soldiers. They are Shion's devoted fans.
Milim and Shion get along decently well. They are often seen picking silly fights with each other such as, who could pick the most sweet potatoes, drawing on each others faces and more. Shion also hates it when Milim calls her 'one-horn lady'
He was a direct enemy to her and Rimuru. His actions led to Falmuth's attack on Tempest, and therefore, also to Shion's death. She was able to get her revenge on him for it by beating him to near-death during Walpurgis.
They fought her during the battle between their and Tempest's forces, but she was too powerful for them to defeat. Even so, Garde was still desperate to defeat her; however, it is revealed that Garde is really Ars in disguise and that the real Garde was murdered.
