"How'd you know which glass to poison?" you and Ghosts target asked coughing as poison started affecting him

You and ghost were undercover, you had poured poison in both glasses without Ghost or your target knowing. Your target had ended up switching the glasses and taking a sip drinking the poison.

"Oh I didn't, I poisoned both." you smile and take a drink from your glass as you had been taking small doses of the same poison everyday for a while while ghost looked at you worried