I am intrigued by the concept of an "eye dropper fill" and the body cavity being the reservoir for the ink.
How does the nib unit, when inserted after a fill, seal so as to prevent ink leakage. ("Surface tension", perhaps ?
Or is the nib unit threaded, and perhaps there is an O-ring seal ? )
And then, if Danny's suggestion gets implemented ( " threaded cap to the body to fill from the end " ), how do you seal that cap to prevent an additional source of leaks ? ( An O-ring, perhaps ? )
This is becoming an interesting pen !