This bogus LastPass imitation will not help you manage your passwords, as the legitimate one would, and will only hinder your browsing experience. Pay attention to how you install software, and you will avoid this. However, you still need to be careful as it could start spreading using software bundles. LastPass was available on the Chrome web store but is not longer accessible. If you obtained the false extension, you are probably experiencing redirects to weird sites promoting dubious programs. An imitation of this program, also called LastPass, has emerged and has been trying to fool users into thinking it is the real one.
LastPass is a password managed application that stores all your passwords.