I get why some readers would be concerned over consent. But take the conversation into context. Yarai seems like an airhead but she is observational since she considered Kaidou's feelings via her expression. And like she said, Kaidou didn't seem discomforted when Yarai brought her face close to...
Don't know why this guy is so sensitive and insecure about two manga characters being in love.
Also why the obsession with genetics? Your genetic sequence will literally not be missed if it suddenly went extinct.