That is the first teaser spot for the series that’s set for a summer 2017 debut, though still formally undated.
The upcoming summer 2017 anime series 18if, which has already been picked up by Funimation, has been teasing out little bits of information for awhile now.
The show is an interesting one as the plan is to work different directors for each episode with Akira Nishimori announced so far.