The domain was run by AdamsNames in the UK, which handle a bunch of other vanity country domains, until the French government noticed, grabbed it back, and put it under the same management as .fr. Once the current vanity registrations expire, you're not likely to see anything in it other than perhaps the research stations located there.
That's Montserrat, a small Caribbean island that is nearly uninhabited due to an erupting volcano. It's been a popular location for "free" p*rn chat since they have +1 numbers and very high rates. Their registry is also run by AdamsNames.
No, they offer third level subdomains in .net.ms, etc., which are fine so long as Cydots feels like doing so. The moment they lose interest, all of those 3rd level domains disappear.
By the way, be sure never to look at IANA's list of country domains at
R's,
John