Man Of A Virtue
Saihyou to Tokeru
At first, the story seems confusing, because the artist didn't show the time skip clearly. On chapter 1 page 8, it says the exhibit runs from "(2015.)11.8 - 2016.1.10", then on chapter 1 page 17, someone is heard on the radio saying "back in 2017", and later Kazushi mentions a memory from 3 years ago, so there must be a 3 year gap between their meeting (page 13) and current time (page 14). Chapter 2 explains what happened between pages 13 and 14 of the first chapter (when Rui recalls their meeting at the exhibit, as Kazushi sleeps soundly), as well as the reasons why it happened, and foreshadows of an impeding separation between them.
Undercover
Young police officer is asked by his boss to go undercover to investigate a potential prostitution ring. Little did he know the kind of things he'll end up doing...IMO this guy is too good at following orders, I'd quit my job right away if I'm asked by my boss to shoot gay videos for some questionable undercover investigation.
Kakkou no Yume
Natsuka has been in love with Hakushima since high school but is afraid of confessing to him, so he has sex with Seno instead. Then when Seno and Hakushima got into an accident, Seno who woke up first pretended to have swapped body with Hakushima to win Natsuka's love. He succeeded until Hakushima regained consciousness 3 months later. Turns out they were all high school classmates, though Natsuka doesn't remember Seno. To pretend to be someone else for the one you love is a very sad thing for both of you, because nothing good will come of it when they wake up. This manga is just a fiction after all.
Kimi no na Wa Star