신세대 means "New Generation" 셔 is a short form of "이시어" 신세대셔 is a composed of 신세대이(다)+시+어 시 is a honorific particle used for senior 어 is an ending particle used to intimate. 신세대셔 means He/she is a kind of new generation. He/she is senior to the speaker. The speaker is intimate with the listener.