I enjoyed the game, but I think I found a few bugs.
Language: Japanese | OS: Windows 11
・Surrendering during the first battle leads to a soft-lock.
・The choices presented after defeating the Giant Weapon are not translated.
・After mutating, the protagonist does not appear during battles against the Giant Weapon, Giant Orange, the three Bunny Girls, the Sniper, the apartment resident, and the two liquor sellers.
・Progression is impossible on the 9th floor of the apartment building.
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・You can use the back-entrance elevator even without clearing the apartment area.
・If you turn back after becoming infected and lose to a police officer zombie, your species reverts to human, and the protagonist's sprite is displayed correctly. (It appears the sprite display bug was unrelated to the specific enemy you fought; my apologies.)
・If you lose to an office worker zombie, the screen remains dark and does not return to normal.
・When you are defeated by an Office Zombie, the "Armed Survivor Event" occurs.
・Even after defeating the zombie that bursts out of the police box, you can still hear voices when passing through the corridor.
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The root cause is likely that events were triggered in an unexpected order. There were inconsistencies between the story/dialogue and the actual situation.