Straighten after colon

So, I recognize that as an effect a bowed unit can be bowed. Can an unbowed unit be straightened as an effect?

Here is the setup: my friend and I were playing IG2 Friday night (I played Honor, and gave him Glory). I had Mirumoto Ayabe (see below) against one of his personalities with 2 attachments. I wanted to straighten his unbowed personality (as an effect of Ayabe's battle ability [ability may be wrong terminology]) and bow his two attachments. Is this possible?

Title Mirumoto Ayabe Battle: Even if Ayabe is bowed: Straighten a target Personality with one or more attachments. Then, bow all attachments in that Personality's unit.

I am confused on certain rulings in the past on what is and is not an effect based strictly on card text.

The way I understand cost and effect is that I need to look for the colon. So, COST : EFFECT. If I am correct, then what follows is...

COST (Even if Ayabe is bowed) : EFFECT (Straighten a target Personality with one or more attachments. Then, bow all attachments in that Personality's unit.)

Am I reading this correctly? Was what I attempted to do possible?

Please advise. G6

EDIT: Thanks for the answers. I appreciate it.

As a side note, I don't always have time to "Read the FAQ" before I get time to post on this forum (say, for instance, when I am at work). I try my best to use the search function and the FAQ when I can, but I am limited in the time I can spend on the internet and therefore getting answers from rules individuals is a much quicker solution for me as it does not require active searching, but a passive request-response mechanism.

Anyhow, once again, thank you for the answers.

I recognize that as an effect a bowed unit can be bowed.

Not exactly. When an effect attempts to bow a bowed card or unit, it fails.

Can an unbowed unit be straightened as an effect?

No, but an unbowed unit can be chosen for an effect that straightens a unit: the effect fails.

I wanted to straighten his unbowed personality (as an effect of Ayabe's battle ability) and bow his two attachments. Is this possible?

Yes, Ayabe's action does not require that the targeted Personality must be unbowed.

See the FAQ about the legality of an action whose effect can't happen: Is an action legal if an effect can't happen?

Am I reading this correctly?

Not exactly: "Even if Ayabe is bowed" is not a cost but a condition. However you are right to look for costs in the constraints block between the two colons (see Card features, Abilities). If a cost exists in the effects block, it will be explicitly stated; for instance see Imperial Decree.