Tokimeki Bakudan

Six men are trapped inside an unfamiliar, abandoned warehouse, each with a mysterious collar around their necks. They have no idea how they got there or what’s happening, but their confusion quickly turns to shock when a plushie dog begins to speak.
The plushie, named Masao, claims to be an AI and announces its bizarre mission: to study the human emotion of tokimeki (heart-pounding). Masao’s “experiment” is simple yet chilling: the men must live together for several days, during which the AI will measure their levels of tokimeki. Those who fail to reach the required emotional threshold will be eliminated from the experiment.
(Source: BLTai.com)