Its not cliff hanger. Bcs all the eneny dying, missile gone so whats more? The rest just the life rai whould enjoy before he dying. Maybe a day a month or a year. We never know. And frankenstein working his ass off to find something he want to know or maybe trying to find how to charged rai‘s life. So its just happy ending end. Since, eternal slumber or dying never cant be stopped for everything which have soul.
Is that it? The epilogue ends with Frankenstein saying smt about finding out what exactly happens (I'm assuming, abt why exactly they survived the nuclear missile), it's strange to just end it there right? I would've been content without that last part but, it's getting on my nerves now.... (ノ`Д´)ノ彡┻━┻