The answer to 'grout greasy' is that grout can become greasy or oily due to a buildup of dirt, soap scum, or cooking oils. This is a common problem in kitchens and bathrooms where the grout is frequently exposed to moisture and grime. The grease can make the grout appear discolored and can be difficult to clean.
To fix greasy grout, you can try a few DIY cleaning methods first. Start by scrubbing the grout with a stiff-bristle brush and a grout cleaner or degreaser. You can also try using a steam cleaner or a mixture of warm water and vinegar. If the grease is particularly stubborn, you may need to re-seal the grout to prevent future buildup. However, if the grout is severely damaged or the problem persists, it's best to call a professional cleaning service to deep clean the grout and provide a long-lasting solution.