w>fasten on
vi +prep obj (= concentrate on) person, subject →
herumhacken auf (+dat) (inf);
his eyes fastened on mine →
er heftete seine Augen auf meine Collins German Dictionary – Complete and Unabridged 7th Edition 2005. © William Collins Sons & Co. Ltd. 1980 © HarperCollins Publishers 1991, 1997, 1999, 2004, 2005, 2007