One 日 in shadow's house shadow was very furious with his ex girlfriend Mandy and was getting ready to destroy everything in sight until...
Terra: *bumps into shadow* ooof!!
shadow: who are u?
Terra: i'm Terra, aren't あなた shadow the hedgehog?
shadow: yes
Terra: omg omg omg!!! your like the best ever sonic is lame i hate him. so do u have a girlfriend
shadow: nope but, あなた are pretty cute
Terra: giggles*
so after that 日 shadow and Terra became closer until marriage and had three children the first two where twins kiera and shadow Jr and their third child Tina came a few months after. shadow couldn't stand being with out Terra and Terra felt the same way.
Terra: shadow i have to go i will be dreaming of u though and cry every second
shadow: i can't sleep until u return
Terra: bye *leaves*
so as life goes on shadow and Terra living their happy lives together married and taking care of 3 kids.