After the Rain, initially known as Sorairo Muffler (そらいろまふらー, Sky-coloured Muffler), is a duet unit between Soraru and Mafumafu.
After the Rain teamed up with the united name Sorairo Muffler in 2014 with the cover of "Umiyuri Kaitei Tan" and quickly became one of their first popular duets together. Their covers are always in Top 4 of Weekly Niconico Utattemita Ranking and got their first No.1 with their cover of "Chuubyou Gekihatsu Boy". As of right now, nearly all of their covers have over one million views.
They host Hikikomoranai Radio (ひきこもらないラジオ), an irregularly occurring podcast where the two of them talk about various subjects.
On September 26, 2015, they announced about their national tour "After the Rain -WINTER TOUR 2015-" which was held in December 2015. Their winter tour started from December 20, 2015 with four lives in Aichi (December 20 at Zepp Nagoya), Osaka (December 21 at Namba Hatch), Fukuoka (December 26 at Zepp Fukuoka) and Tokyo (December 31 at Tokyo Dome City Hall). On November 14, 2015, all tickets of four lives had been sold out and they decided to hold one more live. This final live "Countdown Party 2015-16" also took place in Tokyo Dome City Hall on December 31, 2015. Amatsuki, un:c, Aho no Sakata, Urata, Sekihan and luz were the special guests in their final live.
On January 08, 2016, they announced the new name of their duet unit After the Rain and their first album under this name "Clock Crest Story" saw release on April 13, 2016.
On October 14, 2016, they announced their second national tour, "After the Rain Winter Tour 2016 -WINTER GARDEN-" which was held in December 2016. Their winter tour started from December 18, 2016 with five lives in Sapporo (December 18 at Zepp Sapporo), Osaka (December 23 at Zepp Namba), Tokyo (December 26 at Zepp Tokyo), Aichi (December 28 at Zepp Nagoya), and their final live, "Countdown Party 2016-17" which took place in Tokyo Dome City Hall on December 31, 2016 with Wolpis Kater, Urata, Tonari no Sakata, and luz as their special guests. Due to Soraru's health condition last December 31, the first live before the Countdown Party was postponed and announced the live to be moved on February 23, 2017 by the official ATR Twitter account and official ATR website, however, the Countdown Party still went on without Soraru.
On March 1st, 2017, the duo announced a tentative performance at Budokan Hall, Tokyo that they will be performing as their After the Rain duo. From August 9 to August 10th, After The Rain duo performed a concert 2017 in Nippon Budokan named "AtR -Clockwise / Anti-Clockwise- ". Winter saw to the tour "Winter Tour 2017 -Xmas in Toy Box-" and the 2017-18 Countdown Party with Urata and Sakata as special guests.
In 2018, After the Rain had a summer concert on July 7-8, "Amagoi no Utage/Haregoi no Utage" at the Saitama Super Arena.
After the Rain has also sang anime openings and endings, such as 2017's anime shows Clockwork Planet's ED, Atom: The Beginning's OP, and Reikenzan: Hoshikuzu-tachi no Utage's OP.