Or, if considering another angle where "manko" might be used in an entirely different context or possibly as a placeholder:
The phrase you've given is: "iribitari gal ni manko tsukawasete morau hanashi" Or, if considering another angle where "manko" might
"Get a chair," Kenji muttered, though he shifted his chair back to his desk, turning away from her to focus on his computer. " Kenji muttered