Sensei to Himitsu

1-2) Sensei to Himitsu
Kaji's woken up from his nap hearing popular Tsunoda-sensei getting hot and heavy with another guy! But it's his partner, the plain Aritou-sensei that Kaji can't stop thinking about. Kaji's eyes are being opened as he finds that the needs and dark desires that can bind together lovers aren't always about love...

3-6) Hold me for all of Time
A researcher, Sawatari Kaoru, runs off after finding out that there will be no more funding for his research. As he wanders around he sees an abandoned warehouse where he could use to continue his research with his remaining savings. As he walks inside the building, he meets an arrogant little boy. Surprise ensues as to the boys identity, and the unexpected result of his own research...

Extra) And then...
Continuation of ch.1-2, a little into their future.