No, I am afraid it does not sound at all natural; in fact, I'm not quite sure what it means. In addition, the verb tense is incorrect; it should be in the present tense (like the other verbs in the sentence). Do you mean one of the following?
There is a beautiful clerk who always catches my attention when I am reading comic books.
There is a beautiful clerk who always captures my attention when I am reading comic books.
There is a beautiful clerk who always holds my attention when I am reading comic books.
I think the student meant grabs. There may be a better word here, but grasped is not it. Also past tense doesn't work in this present tense context.
The sentence is also strange in (apparently) not saying where. If the word there is not emphasized, it does not mean "in that place", so I am looking for some adverb of place such as "There is a beautiful clerk in that store who ...", assuming a store has already been mentioned.
I think you're probably right about "grabs." I also know what you mean about the location of the beautiful clerk! I kept wondering if she was a character in one of the comic books! Somehow the whole idea of the comic books is out of place.