1) When a young dashing teacher visits his pupil's home, he encounters his old classmate who works now as a debt collector. The friend has looked after the pupil whose mother ran away and only left him a heavy debt. The teacher and the debt collector return to their former love-relationship...

2) A very nice medicine salesman visits the room of a doctor who caught the flu. The doctor buys a medicine in return for the salesman's sexual service. But the salesman turns out to be an old acquaintance with whom he had had a sexual relationship in the past and he tries to interfere with the doctor's engagement with the hospital director's daughter

3) An office worker who got downsized is picked up by a clever student and changes into a very sexy guy. He tries to take revenge on his old colleague who stole his lover but the colleague turns out to be an ex-lover of the student...

4) The lonely student who has a somehow demonic desire is confined in a room by a very sound and popular teacher who decides to commit suicide. With this teacher's so strong obsession, the student forgets his hatred for society...

(from B-U)