Monk Skill Quest

Apprentice Monk- talk to him while you're at 0 weight.

Ki Translation Quest

Enter the building at the center of the St. Capitolina Abbey (prt_monk 192, 171), and greet the Monk there (monk_test 316, 68). Next, a 3 o'clock from here, outside the building, you should see an NPC "Apprentice Monk" (prt_monk 270, 197). If you talk to him with 0 Weight, he will teach you Ki Translation.

Ki Explosion Quest

Head to the Monk (monk_test 316, 68) in the center building of the St. Capitolina Abbey (prt_monk 192, 171). He requires two things before he will teach you the skill.

First, you must learn Ki Translation, and second, you must gather the following items dropped by Mandragoras:

20x Stems
3x Shoots

...and he will then teach you Ki Explosion.