After black played the marked stone you couldn't blink an eye before white administered this winning combination.
(;SZ[19]AW[ma]AW[db]AW[kb]AW[nb]AW[pb]AW[rb]AW[dc]AW[jc]AW[kc]AW[nc]AW[qc]AW[bd]AW[cd]AW[jd]AW[nd]AW[rd]AW[de]AW[ge]AW[ie]AW[je]AW[ke]AW[le]AW[me]AW[qe]AW[re]AW[ef]AW[ff]AW[hf]AW[if]AW[jf]AW[kf]AW[mf]AW[rf]AW[gg]AW[hg]AW[kg]AW[mg]AW[ng]AW[og]AW[rg]AW[hh]AW[ih]AW[kh]AW[qh]AW[rh]AW[fi]AW[hi]AW[oi]AW[qi]AW[ij]AW[rj]AW[ck]AW[ok]AW[qk]AW[rk]AW[ol]AW[pl]AW[ql]AW[bm]AW[dm]AW[rm]AW[cn]AW[mn]AW[sn]AW[co]AW[do]AW[mo]AW[ro]AW[cp]AW[jp]AW[lp]AW[dq]AW[gq]AW[hq]AW[jq]AW[kq]AW[mq]AW[pq]AW[qq]AW[br]AW[cr]AW[dr]AW[hr]AW[ir]AW[kr]AW[nr]AW[or]AW[pr]AB[ka]AB[la]AB[oa]AB[eb]AB[hb]AB[jb]AB[lb]AB[ob]AB[ec]AB[gc]AB[ic]AB[lc]AB[oc]AB[hd]AB[id]AB[kd]AB[ld]AB[pd]AB[qd]AB[be]AB[he]AB[pe]AB[lf]AB[nf]AB[pf]AB[qf]AB[cg]AB[eg]AB[fg]AB[ig]AB[jg]AB[lg]AB[pg]AB[qg]AB[fh]AB[gh]AB[jh]AB[lh]AB[mh]AB[oh]AB[ph]AB[ci]AB[gi]AB[ii]AB[ji]AB[ki]AB[ni]AB[pi]AB[ri]AB[fj]AB[hj]AB[pj]AB[qj]AB[gk]AB[hk]AB[pk]AB[nl]AB[cm]AB[mm]AB[om]AB[pm]AB[qm]AB[dn]AB[en]AB[ln]AB[nn]AB[on]AB[qn]AB[rn]AB[eo]AB[jo]AB[ko]AB[lo]AB[qo]AB[dp]AB[ep]AB[gp]AB[hp]AB[ip]AB[kp]AB[pp]AB[qp]AB[bq]AB[cq]AB[fq]AB[iq]AB[oq]AB[rq]AB[er]AB[gr]AB[qr]AB[rs]TR[oh]GM[1]FF[4]CA[UTF-8]AP[CGoban:2]ST[2]RU[Japanese]KM[0.00]PW[White]PB[Black]
(;W[nh];B[oj];W[mi];B[li];W[mj]
(;B[nk];W[jj]C[The horrors of aji.RIGHT])
(;B[jk]
(;W[nk]TR[ni]TR[oj]TR[pk]TR[pj]TR[qj]TR[pi]TR[ph]TR[oh]TR[pg]TR[qg]TR[qf]TR[pf]TR[nf]TR[pe]TR[pd]TR[qd]TR[oc]TR[ob]TR[oa]C[The marked stones now have issues.RIGHT])
(;W[lj]C[];B[kj];W[nk]TR[pk]TR[pj]TR[qj]TR[oj]TR[ni]TR[oh]TR[pi]TR[ph]TR[pg]TR[qg]TR[qf]TR[pf]TR[nf]TR[pe]TR[pd]TR[qd]TR[oc]TR[ob]TR[oa]C[The marked stones now have issues.RIGHT])))
(;W[li];B[mi];W[lj];B[jj]
(;W[nj];B[mj];W[mk];B[oj];W[nk];B[lk];W[ml];B[ll])
(;W[nk];B[mj];W[mk];B[lk];W[ll];B[kk];W[ml];B[km])))