Watching this about 2 years after watching the series feels like I just unlocked some heavy PTSD that I had no idea I had. This is basically the responses from the gang to the letter's that Menma wrote. This digs into your heart and I couldn't help tearing up. If you loved the series, this doesn't add much but hearing their reactions as they write letters back to her is just so beautiful. I highly recommend watching this if you enjoyed the series. It feels like Menma is still with them even after they "found" her. It made me end up rewatching the ending ofthe series to remind myself of the letters and it hits so much more powerfully just with that much more alone.