In Kamisekai there are a few moves the GM can leverage against the party.

Require the players to make up their minds in a hurry!
Pick an arbitrary length of time between 5 to 15 minutes. Name (or randomly select) a player to give the final answer for the group. Pose your question to them and demand an answer within that time span.
If they decide: You have your answer, proceed!
If they fail to decide:
Hand out a punishment based on severity. Examples:

• A debuff or ailment that affects one, all, or random players.
• The players suffer a disadvantage during or before an enemy approach.
• The difficulty of future encounters increases.
• Diminished session rewards.
• Any other evil thing you can think of.

Players should be encouraged to avoid RP during this time to discuss and reach a decision as quickly as possible.