A topic from AEG's L5R CCG Rules forum, copied for Oracle of the Void from a copy of the forum saved in October 2015, so pages it didn't save are missing. Players' names are left out; the rules officials are named. Rulings are as they stood on these dates; later rulings, the rulebooks and the Rules Archive may differ.
A player, 10 April 2013
Can I use the ability on Suiteru no Oni if it's my only personality in play? I'd imagine so, since at the announcement of the action, I do have a personality for the followers to attach (somewhat similar to casting Seeking the Way with your lone attacking personality, but not quite).
Relevant text: Open: Destroy your target unbowed Personality: Create a number of 1F Shadowlands • Nonhuman • Oni Followers equal to his Chi. Attach them to one or more of your Personalities. Lose Honor equal to the number of Followers this created.
A player, 10 April 2013
Kicking this for discussion.
A player, 19 April 2013
At the time of announcing the action, you had a legal target for attaching the followers, so it is technically legal to announce.