Yamada-kun and the Seven Witches

Yamada-kun and the Seven Witches is a romantic, supernatural comedy manga series that received an anime adaptation which aired in 2015.

The story follows Ryu Yamada, a delinquent at Suzaku High School who one day falls down the stairs onto ace student Urara Siraishi. He awakens to find himself in her body, and they discover that kissing triggers the body swap.

Learning of their ability, the student council vice-principal Toranosuke Miyamura recruits them to join the dying Supernatural Studies Club. After unearthing the legend of the Seven Witches of Suzaku High; seven female students who have obtained different powers that are activated by a kiss, the club decides to find the identities of these witches.

An animated PV was released in 2013, well before the tv series aired, as well as an OAD duology that was released in 2014 and 2015.

PV
Yamada unbuttons his pants, the Club members are seen at the beach, and both Yamada's and Miyamura's shirts fly up while they're sleeping.

OAD Announcement
'Miyamura' inspects his body.

OAD 1
Igarashi and Miyamura are at a hot spring, and Yamada's shirt flies up while he's sleeping.

Episode 1
Miyamura examines himself while in Yamada's body.

Episode 2
'Miyamura' finds a surprise on his body, and Yamada is seen without a shirt on in the endcard.

Episode 6
The Supernatural Studies Club has fun at the beach.