Japanese by Example
Learning through examples in manga

Presuming the reason for the café's name with 〜だろう

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Cocoa asks why the café is named “Rabbit House”.

リゼ:
「そりゃティッピーがこの(みせ)のマスコットだからだろう?」
"That's because (the rabbit) Tippy is the shop's mascot, isn't it?"