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Hakusen Academy is a super elite high school where students are divided by their academic grades from classes A to F. On top of all these classes is the S·A (Special A) class where only the top seven of the school can enter. Their uniform, classroom, and classes are different from those of the "regular" students and a mere sight of them can already be a very rare thing for others. Jun and Kei are both members of this class.
Jun and Kei are, in a way, opposite. Jun is an extremely shy boy who hardly socializes and tends to be with Megumi and Ryuu (another member of the S·A) all the time. Kei is a confident student who, aside from wealth, not only possesses intellect but also physical looks and capabilities that make girls go head over heels. Just like the rest of the S·A class, Jun and Kei are good friends.
As the story progresses it is revealed that Jun has a concealed identity which is pretty liberated and very popular to the girls. It came as a shock to everyone when it freed itself after Jun was kissed by Sakura, a girl who has a deep crush on him.
In episode 20 of the series, the "inner Jun" returns and finds himself in front of Kei and hugs him. Sakura tells Kei to hold him so that he won't escape. But suddenly, Jun kisses Kei... to free himself out of his grasp.
Inexcusable Deliverance is quite straightforward for a title. In other words, it could be "untolerable freedom". It basically refers to how Jun was able to establish a different and funny relationship with Kei via his hidden self.