Aguilar (w) made a little misread here in a game already won; he thought he only could get seki, but he can kill black. It shouldn't be too hard to figure out.
(;AW[jp]AB[no]AB[nn]AW[op]AW[oo]AW[on]AB[po]AB[qp]AB[qq]AB[rq]AW[fq]AW[hq]AW[iq]AW[jq]AW[kp]AW[lo]AW[mo]AB[np]AB[mp]AB[lq]AB[kq]AW[pq]AW[oq]AW[nq]AB[pp]AW[pn]AW[qm]AW[qo]AW[rn]AW[rl]AW[sm]AB[ql]AB[pl]AB[pm]AB[om]AB[nm]AB[ol]AB[ok]AB[oj]AB[pj]AW[pk]AW[qk]AW[qi]AW[qj]AW[rj]AW[pi]AW[oi]AW[ni]AW[nj]AW[mj]AW[nk]AB[mk]AB[ml]AW[nh]AB[mh]AB[mi]AB[li]AB[lh]AB[ki]AB[lj]AB[kj]AB[jj]AB[ij]AB[hj]AB[hh]AB[ih]AW[ji]AW[jh]AW[kh]AW[jg]AW[ig]AW[hg]AW[if]AW[gh]AW[fh]AW[fi]AW[fj]AW[ej]AW[gj]AW[gk]AW[hk]AW[gl]AW[gm]AW[fm]AW[gn]AW[go]AW[gp]AB[hp]AB[ip]AB[hn]AB[in]AB[kn]AB[ik]AB[hm]AB[im]AB[hl]AB[km]AB[jl]AW[jm]AW[jn]AW[jo]AW[mr]AW[rr]AW[qr]AB[pr]AW[mg]AW[lg]LB[mn:1]C[Aguilar (7d) played '1' here (against boobgooper 5k Jan 2007, on KGS), but later admitted he overlooked killing black.]AP[goproblems]
(;W[kk];B[ln]
(;W[mn];B[mm]
(;W[ll];B[kl];W[lk]C[Eventually the marked stones will have connect at M7, and then the group is down to one eye !RIGHT]MA[mk]MA[ml]MA[mm]MA[nm]MA[nn]MA[no]MA[np]MA[mp]MA[lq]MA[kq]MA[om]MA[ol]MA[ok]MA[oj]MA[pj]MA[pl]MA[ql]MA[pm])
(;W[kl];B[lk]
(;W[ll]C[Yep !RIGHT])
(;W[ko]C[Yes!RIGHT]))
(;W[lk];B[ll]))
(;W[ll];B[mn]
(;W[lm];B[kl])
(;W[kl];B[lm])))
(;W[nl];B[kk];W[mm];B[mn])
(;W[mm];B[kk];W[lm];B[ll])
(;W[lm];B[kk];W[ll];B[ln];W[mn];B[mm])
(;W[mn];B[kk]
(;W[lm];B[ll])
(;W[ll];B[lm];W[mm];B[nl]))
(;W[kl];B[kk];W[ll];B[lm])
(;W[ll];B[kk];W[lm];B[ln];W[mm];B[mn];W[nl];B[lk])
(;W[kr])
(;W[lr])
(;W[ln];B[kk];W[lm];B[ll])
(;W[jk];B[kk])
(;W[lk];B[kk];W[ll];B[lm])
(;W[io];B[kk])
(;W[ho];B[kk]))