Notes:  
I had a sore throat. I had to go shopping. This was on my mind when I returned. 'nuff said! 

He sneezed violently and, for a brief moment, saw the street some dozen meters below him tilt. Damn, he really caught something. After his vision cleared enough, he decided to alter his modus operandi in favor of waiting in the target's apartment rather than in front of it. At least, he would get out of the rain, then, and not risk falling off the ledge. 
     Forty minutes later, he was warm, his nose was running, and his voice was pretty much gone. So much for incantations, he thought sourly, and contemplated if there was a possibility to relay at least the headaches to the Tree. If the target didn't get home soon, he would have to rely on the Beretta he had stuffed into the depths of his pockets somewhere, in case of more mundane problems in the less well-situated parts of town. 
     Shooting. Seishiro ground his teeth. That would certainly kill his reputation along with the target. Could headaches throb down into your teeth? He drew a deep, hissing breath, felt his throat hot and dry and - on suspicion - tested his voice. 
     croak 
     Please?! 
     Tested his voice. 
     croa--- 
     ...!!?! 
     He blinked. The weak shine from the streetlights outside was painfully bright behind his dark glasses. His head throbbed, his teeth ached, his nose - "Achoo!" - and his voice was gone, too. That was it. He couldn't execute the job today. No chance that he'd survive dealing with sakanagi in this condition. 
     He left the apartment through the door -- in dislike of risking the facade again in his condition -- and just in time drew his maboroshi around himself when his target came up the stairs. "Aaachoo." 

*

Takatori Junichi frowned. Hadn't someone sneezed right by his side just now? But there was no one in the hallway. "Hello? Is there somebody?" He waited. After a moment, he shrugged and continued up to his apartment. 

Two days later, Junichi felt kind of weak and the throbbing headache he'd had for most of the day now wouldn't cease. When his nose started to run and his voice vanished, he excused himself from the office and went to see a doctor. With a prescription of Tamiflu and a one-week-leave, he fell into his bed at home soon afterwards. 

*

Six days later, an astonished, just-about-recovered Seishiro who was just contemplating going and disposing Takatori for good, received the following fax: 

CONFIRMATION OF EXECUTION OF CONTRACT NO. 126/G BY UNUSUAL MEANS.  
THE PAYMENT HAS BEEN TRANSFERED TO YOUR BANKACCOUNT. 
~IHA-47-3 
P.S.: PLEASE ABSTAIN FROM USING BIOLOGICAL AGENTS IN THE FUTURE. 

End. (Aachoo!)