[ Tsubasa mulls it over in his head a bit, a hand resting under his chin. ]

I think that whatever name you want to go by is fine, Sakura-san. Even if you might have bad memories associated with the 'Matou' name, you still consider it as a part of who you are. Similarly to how Kimihiro doesn't use the name 'Tsubasa', or 'Syaoran'.

If you don't feel like you have a claim to your old name, I think that's fine. It doesn't change who you are as a person.