Do you know Mishka's past? If you have had him only 3 weeks and he is 10 months old where was he during that time? If he was a stray. maybe he is just fearful that he will not have food on a regular basis.....a couple of mine ( when they first got here )always seemed worried that this might be their last meal. So they ate a lot more than average. They do tend to level off after a while, but some are just more vocal than others. Add on top of that the fact that it is a kitten probably in the same stage as a teen-age boy (and you KNOW how they can eat!)