Sonic X Mina relationship and story

Mina was first found by Sonic while she was mourning the loss of her mother in the recently retaken Robotropolis during Dr. Eggman's takeover. When Sonic's Uncle Chuck becomes a robot slave for the dictator once again, Sonic recklessly stole the Sword of Acorns to restore his uncle's free will. Along the way to Robotropolis, he ran into Mina, who lectured Sonic about stealing the sword. The two were ambushed by Eggman's COMbots, and Sonic chose to save Mina at the cost of losing the sword. Feeling grateful for saving her life, Mina provided an alibi for Sonic when the King's Secret Serivce started to suspect him for the theft. (StH: #76, #93)

When Mina finally mustered the courage to kiss Sonic, she was turned away, as Sonic was still in love with Sally. Meanwhile, Sally, who was locked away within the palace for a while due to her royal duties, finally decided to make an exit to see Sonic again. Posing as a servant girl, she exited the palace, arriving just in time to see the kiss between Mina and Sonic, causing her to believe Sonic had moved on. (StH: #99)

Some time later, Mina was finally ready to join the Freedom Fighters -- if only so she could spend more time with Sonic. However, on her first mission, she discovered that she lacked the courage to act when engaged in conflict. She then realized she should not join the Freedom Fighters just for Sonic, and that she was unfit for the lifestyle. Shortly after, Mina discovers her talent as a singer when it gains Sonic's attention. With a little motivation from Sonic, Mina decides to start singing professionally. (StH: #120, #121)

Mina's singing career leads Sonic to slowly develop emotional feelings for her. However, just before Mina had the chance to ask Sonic out on a date, Sally was kidnapped by the fugitive Nack the Weasel. Mina embarks on a rescue mission with Sonic to save the princess, but is heartbroken when Sonic and Sally realize their true love for each other and kiss. During their moment of passion, Mina notices Nack ready to shoot Sally before making his escape. Mina takes the bullet, and tells Sonic she loves him before passing out. She is rushed to the hospital by Sonic and made a full recovery, though felt sad at the discovery Sonic loved Sally. (StH: #122, #123)

After Sonic's unexpected adventure in outer space (which strands him away from Mobius for a year), he returned home to find that his friends and family have all accepted his apparent death. Like Sally, Mina had also moved on while Sonic was away, and is dating her record manager, Ash. Although Mina briefly juggles her feelings for Sonic when he returns, she is quickly forced to reconcile with Ash when he is injured by a Bomb while trying to protect her. According to her, while she would always have a place in her heart for Sonic, she loves Ash, and not him. (StH: #154)