Is POS coin safe from attackers ?

[funcryptoco]

I read a lot of 51% attack that can be happen, however the point is not clear to me what if we have 101 account each account have 1 coin and another account have 100 coins, is that make 51% for 101 account?
what if this 101 account created by attackers to have %51?

[Byzantium101]

What you are describing is an attack on a PoW network really, the PoS is much less sensible to this type of attack, particularly if the nodes are selected carefully and not left to chance.