Nl25 6max, Call this river vs the maniac?

[Yenool]

So would you call this river vs the table maniac? this guy has been to the river 13 hands in 30 and has bet the river 12 times out of 13, showing complete bluffs twice and bottom pair at least twice. Do you call this with 99?

Poker Room skin
No Limit Holdem Ring game
Blinds: $0.15/$0.25
6 players


Stack sizes:
Yenool: $35.85
UTG+1: $36.20
CO: $20.65
Button: $36.95
SB: $12.50
BB: $20.55

Pre-flop: (6 players) Yenool is UTG with
Yenool raises to $1, UTG+1 folds, CO calls, Button calls, 2 folds.

Flop: ($3.4, 3 players)
Yenool bets $2.5, CO folds, Button calls.

Turn: ($8.4, 2 players)
Yenool checks, Button checks.

River: ($8.4, 2 players)
Yenool checks, Button bets $3, Yenool??


... Here is a hand just to give you some idea how bad this guy is:

Poker Room skin
No Limit Holdem Ring game
Blinds: $0.15/$0.25
5 players


Stack sizes:
UTG: $20.95
CO: $54.50
Button: $20.55
Yenool: $29.35
BB: $25.00

Pre-flop: (5 players) Yenool is SB with
UTG folds, CO calls, Button folds, Yenool calls, BB checks.

Flop: ($0.75, 3 players)
Yenool bets $0.5, BB folds, CO calls.

Turn: ($1.75, 2 players)
Yenool bets $1, CO calls.

River: ($3.75, 2 players)
Yenool bets $2, CO raises to $5, Yenool calls.

Results:
Final pot: $13.75
CO shows 10C 2H
Yenool shows KC10S

[Zmej]

[Yenool]

[adamh]

[laynegt]