David Plaisance, 63, began sending the correspondence and gifts in 2001, with the parcels always arriving at the woman's office, even after she changed jobs in 2010, according to an East Baton Rouge Sheriff's Office report.
The woman didn't know Plaisance and never responded to his letters.
She contacted the Sheriff's Office in May after Plaisance's letters began "describing what she was wearing, and advising that he was watching her exit and enter her place of employment," the report says. The woman showed a detective a box containing hundreds of letters.
The detective ordered Plaisance to stop writing the woman and warned that he would be arrested if he didn't comply, the report says. But the victim called deputies again on Thursday, saying more letters had arrived from Plaisance.
When deputies found him at his home, Plaisance said: "I'm not doing anything wrong. I'm only sending letters to my girlfriend!", according to the report.
Plaisance was booked into Parish Prison on a count of stalking. He remained in jail Friday evening in lieu of $2,500 bail, according to online records.